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package algebird

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Package Members

  1. package immutable
  2. package macros
  3. package matrix
  4. package monad
  5. package mutable
  6. package statistics

Type Members

  1. abstract class AbstractApplicative[M[_]] extends Applicative[M]

    For use from Java/minimizing code bloat in scala

  2. trait AbstractEventuallyAggregator[A, E, O, C] extends Aggregator[A, Either[E, O], C]
  3. abstract class AbstractFunctor[M[_]] extends Functor[M]

    For use from Java/minimizing code bloat in scala

  4. abstract class AbstractGroup[T] extends Group[T]
  5. abstract class AbstractMonad[M[_]] extends Monad[M]

    For use from Java/minimizing code bloat in scala

  6. abstract class AbstractMonoid[T] extends Monoid[T]
  7. abstract class AbstractRing[T] extends Ring[T]
  8. abstract class AbstractSemigroup[T] extends Semigroup[T]
  9. class AdaptiveCache[K, V] extends StatefulSummer[Map[K, V]]

    This is a wrapper around SummingCache that attempts to grow the capacity by up to some maximum, as long as there's enough RAM.

    This is a wrapper around SummingCache that attempts to grow the capacity by up to some maximum, as long as there's enough RAM. It determines that there's enough RAM to grow by maintaining a SentinelCache which keeps caching and summing the evicted values. Once the SentinelCache has grown to the same size as the current cache, plus some margin, without running out of RAM, then this indicates that we have enough headroom to double the capacity.

  10. sealed trait AdaptiveVector[V] extends IndexedSeq[V]

    An IndexedSeq that automatically switches representation between dense and sparse depending on sparsity Should be an efficient representation for all sizes, and it should not be necessary to special case immutable algebras based on the sparsity of the vectors.

  11. case class AdjoinedUnit[T](ones: BigInt, get: T) extends Product with Serializable

    This is for the case where your Ring[T] is a Rng (i.e.

    This is for the case where your Ring[T] is a Rng (i.e. there is no unit).

    See also

    http://en.wikipedia.org/wiki/Pseudo-ring#Adjoining_an_identity_element

  12. class AdjoinedUnitRing[T] extends Ring[AdjoinedUnit[T]]
  13. case class AffineFunction[R](slope: R, intercept: R) extends Serializable with Product

    Represents functions of the kind: f(x) = slope * x + intercept

  14. class AffineFunctionMonoid[R] extends Monoid[AffineFunction[R]]

    This feeds the value in on the LEFT!!! This may seem counter intuitive, but with this approach, a stream/iterator which is summed will have the same output as applying the function one at a time in order to the input.

    This feeds the value in on the LEFT!!! This may seem counter intuitive, but with this approach, a stream/iterator which is summed will have the same output as applying the function one at a time in order to the input. If we did the "lexigraphically correct" thing, which might be (f+g)(x) = f(g(x)) then we would wind up reversing the list in the sum. (f1 + f2)(x) = f2(f1(x)) so that: listOfFn.foldLeft(x) { (v, fn) => fn(v) } = (Monoid.sum(listOfFn))(x)

  15. trait Aggregator[-A, B, +C] extends Serializable

    This is a type that models map/reduce(map).

    This is a type that models map/reduce(map). First each item is mapped, then we reduce with a semigroup, then finally we present the results.

    Unlike Fold, Aggregator keeps it's middle aggregation type externally visible. This is because Aggregators are useful in parallel map/reduce systems where there may be some additional types needed to cross the map/reduce boundary (such a serialization and intermediate storage). If you don't care about the middle type, an _ may be used and the main utility of the instance is still preserved (e.g. def operate[T](ag: Aggregator[T, _, Int]): Int)

    Note, join is very useful to combine multiple aggregations with one pass. Also GeneratedTupleAggregator.fromN((agg1, agg2, ... aggN)) can glue these together well.

    This type is the the Fold.M from Haskell's fold package: https://hackage.haskell.org/package/folds-0.6.2/docs/Data-Fold-M.html

  16. class AggregatorApplicative[I] extends Applicative[[O]Aggregator[I, _, O]]

    Aggregators are Applicatives, but this hides the middle type.

    Aggregators are Applicatives, but this hides the middle type. If you need a join that does not hide the middle type use join on the trait, or GeneratedTupleAggregator.fromN

  17. final case class AndVal(get: Boolean) extends AnyVal with Product with Serializable
  18. trait Applicative[M[_]] extends Functor[M]

    Simple implementation of an Applicative type-class.

    Simple implementation of an Applicative type-class. There are many choices for the canonical second operation (join, sequence, joinWith, ap), all equivalent. For a Functor modeling concurrent computations with failure, like Future, combining results with join can save a lot of time over combining with flatMap. (Given two operations, if the second fails before the first completes, one can fail the entire computation right then. With flatMap, one would have to wait for the first operation to complete before failing it.)

    Laws Applicatives must follow: map(apply(x))(f) == apply(f(x)) join(apply(x), apply(y)) == apply((x, y)) (sequence and joinWith specialize join - they should behave appropriately)

    Annotations
    @implicitNotFound()
  19. class ApplicativeGroup[T, M[_]] extends ApplicativeMonoid[T, M] with Group[M[T]]

    Group and Ring ARE NOT AUTOMATIC.

    Group and Ring ARE NOT AUTOMATIC. You have to check that the laws hold for your Applicative. If your M[_] is a wrapper type (Option[_], Some[_], Try[_], Future[_], etc...) this generally works.

  20. class ApplicativeMonoid[T, M[_]] extends ApplicativeSemigroup[T, M] with Monoid[M[T]]

    This is a Monoid, for all Applicatives.

  21. class ApplicativeOperators[A, M[_]] extends FunctorOperators[A, M]

    This enrichment allows us to use our Applicative instances in for expressions: if (import Applicative._) has been done

  22. class ApplicativeRing[T, M[_]] extends ApplicativeGroup[T, M] with Ring[M[T]]

    Group and Ring ARE NOT AUTOMATIC.

    Group and Ring ARE NOT AUTOMATIC. You have to check that the laws hold for your Applicative. If your M[_] is a wrapper type (Option[_], Some[_], Try[_], Future[_], etc...) this generally works.

  23. class ApplicativeSemigroup[T, M[_]] extends Semigroup[M[T]]

    This is a Semigroup, for all Applicatives.

  24. case class Approximate[N](min: N, estimate: N, max: N, probWithinBounds: Double)(implicit numeric: Numeric[N]) extends ApproximateSet[N] with Product with Serializable
  25. case class ApproximateBoolean(isTrue: Boolean, withProb: Double) extends ApproximateSet[Boolean] with Product with Serializable
  26. abstract class ArrayBufferedOperation[I, O] extends Buffered[I, O]
  27. class ArrayGroup[T] extends ArrayMonoid[T] with Group[Array[T]]

    Extends pair-wise sum Array monoid into a Group negate is defined as the negation of each element of the array.

  28. class ArrayMonoid[T] extends Monoid[Array[T]]

    Pair-wise sum Array monoid.

    Pair-wise sum Array monoid.

    plus returns left[i] + right[i] for all array elements. The resulting array will be as long as the longest array (with its elements duplicated) zero is an empty array

  29. case class AveragedValue(count: Long, value: Double) extends Product with Serializable

    Tracks the count and mean value of Doubles in a data stream.

    Tracks the count and mean value of Doubles in a data stream.

    Adding two instances of AveragedValue with + is equivalent to taking an average of the two streams, with each stream weighted by its count.

    The mean calculation uses a numerically stable online algorithm suitable for large numbers of records, similar to Chan et. al.'s parallel variance algorithm on Wikipedia. As long as your count doesn't overflow a Long, the mean calculation won't overflow.

    count

    the number of aggregated items

    value

    the average value of all aggregated items

    See also

    MomentsGroup.getCombinedMean for implementation of +

  30. sealed abstract class BF[A] extends Serializable

    Bloom Filter data structure

  31. case class BFHash[A](numHashes: Int, width: Int)(implicit hash: Hash128[A]) extends Product with Serializable
  32. case class BFInstance[A](hashes: BFHash[A], bits: BitSet, width: Int) extends BF[A] with Product with Serializable
  33. case class BFItem[A](item: A, hashes: BFHash[A], width: Int) extends BF[A] with Product with Serializable

    Bloom Filter with 1 value.

  34. case class BFSparse[A](hashes: BFHash[A], bits: EWAHCompressedBitmap, width: Int) extends BF[A] with Product with Serializable
  35. case class BFZero[A](hashes: BFHash[A], width: Int) extends BF[A] with Product with Serializable

    Empty bloom filter.

  36. sealed abstract class Batched[T] extends Serializable

    Batched: the free semigroup.

    Batched: the free semigroup.

    For any type T, Batched[T] represents a way to lazily combine T values as a semigroup would (i.e. associatively). A Semigroup[T] instance can be used to recover a T value from a Batched[T].

    Like other free structures, Batched trades space for time. A sum of batched values defers the underlying semigroup action, instead storing all values in memory (in a tree structure). If an underlying semigroup is available, Batched.semigroup and Batch.monoid can be configured to periodically sum the tree to keep the overall size below batchSize.

    Batched[T] values are guaranteed not to be empty -- that is, they will contain at least one T value.

  37. class BatchedMonoid[T] extends BatchedSemigroup[T] with Monoid[Batched[T]]

    Compacting monoid for batched values.

    Compacting monoid for batched values.

    This monoid ensures that the batch's tree structure has fewer than batchSize values in it. When more values are added, the tree is compacted using m.

  38. class BatchedSemigroup[T] extends Semigroup[Batched[T]]

    Compacting semigroup for batched values.

    Compacting semigroup for batched values.

    This semigroup ensures that the batch's tree structure has fewer than batchSize values in it. When more values are added, the tree is compacted using s.

  39. case class BloomFilterAggregator[A](bfMonoid: BloomFilterMonoid[A]) extends MonoidAggregator[A, BF[A], BF[A]] with Product with Serializable
  40. case class BloomFilterMonoid[A](numHashes: Int, width: Int)(implicit hash: Hash128[A]) extends Monoid[BF[A]] with BoundedSemilattice[BF[A]] with Product with Serializable

    Bloom Filter - a probabilistic data structure to test presence of an element.

    Bloom Filter - a probabilistic data structure to test presence of an element.

    Operations 1) insert: hash the value k times, updating the bitfield at the index equal to each hashed value 2) query: hash the value k times. If there are k collisions, then return true; otherwise false.

    http://en.wikipedia.org/wiki/Bloom_filter

  41. trait Buffered[I, O] extends Serializable

    Represents something that consumes I and may emit O.

    Represents something that consumes I and may emit O. Has some internal state that may be used to improve performance. Generally used to model folds or reduces (see BufferedReduce)

  42. trait BufferedReduce[V] extends Buffered[V, V]

    This never emits on put, you must call flush designed to be use in the stackable pattern with ArrayBufferedOperation

  43. class BufferedSumAll[V] extends ArrayBufferedOperation[V, V] with StatefulSummer[V] with BufferedReduce[V]
  44. final case class Bytes(array: Array[Byte]) extends Serializable with Product

    A wrapper for Array[Byte] that provides sane implementations of hashCode, equals, and toString.

    A wrapper for Array[Byte] that provides sane implementations of hashCode, equals, and toString. The wrapped array of bytes is assumed to be never modified.

    Note: Unfortunately we cannot make Bytes a value class because a value class may not override the hashCode and equals methods (cf. SIP-15, criterion 4).

    Alternatives

    Instead of wrapping an Array[Byte] with this class you can also convert an Array[Byte] to a Seq[Byte] via Scala's toSeq method:

    val arrayByte: Array[Byte] = Array(1.toByte)
    val seqByte: Seq[Byte] = arrayByte.toSeq

    Like Bytes, a Seq[Byte] has sane hashCode, equals, and toString implementations.

    Performance-wise we found that a Seq[Byte] is comparable to Bytes. For example, a CMS[Seq[Byte]] was measured to be only slightly slower than CMS[Bytes] (think: single-digit percentages).

    array

    the wrapped array of bytes

    See also

    MinHasher

  45. sealed abstract class CMS[K] extends Serializable with CMSCounting[K, CMS]

    A Count-Min sketch data structure that allows for counting and frequency estimation of elements in a data stream.

    A Count-Min sketch data structure that allows for counting and frequency estimation of elements in a data stream.

    Tip: If you also need to track heavy hitters ("Top N" problems), take a look at TopCMS.

    Usage

    This example demonstrates how to count Long elements with CMS, i.e. K=Long.

    Note that the actual counting is always performed with a Long, regardless of your choice of K. That is, the counting table behind the scenes is backed by Long values (at least in the current implementation), and thus the returned frequency estimates are always instances of Approximate[Long].

    K

    The type used to identify the elements to be counted.

    Example:
    1. // Creates a monoid for a CMS that can count `Long` elements.
      val cmsMonoid: CMSMonoid[Long] = {
        val eps = 0.001
        val delta = 1E-10
        val seed = 1
        CMS.monoid[Long](eps, delta, seed)
      }
      
      // Creates a CMS instance that has counted the element `1L`.
      val cms: CMS[Long] = cmsMonoid.create(1L)
      
      // Estimates the frequency of `1L`
      val estimate: Approximate[Long] = cms.frequency(1L)
  46. case class CMSAggregator[K](cmsMonoid: CMSMonoid[K]) extends MonoidAggregator[K, CMS[K], CMS[K]] with Product with Serializable

    An Aggregator for CMS.

    An Aggregator for CMS. Can be created using CMS.aggregator.

  47. trait CMSCounting[K, C[_]] extends AnyRef

    A trait for CMS implementations that can count elements in a data stream and that can answer point queries (i.e.

    A trait for CMS implementations that can count elements in a data stream and that can answer point queries (i.e. frequency estimates) for these elements.

    Known implementations: CMS, TopCMS.

    K

    The type used to identify the elements to be counted.

    C

    The type of the actual CMS that implements this trait.

  48. case class CMSHash[K](a: Int, b: Int, width: Int)(implicit evidence$30: CMSHasher[K]) extends Serializable with Product
  49. trait CMSHasher[K] extends Serializable

    The Count-Min sketch uses d (aka depth) pair-wise independent hash functions drawn from a universal hashing family of the form:

    The Count-Min sketch uses d (aka depth) pair-wise independent hash functions drawn from a universal hashing family of the form:

    h(x) = [a * x + b (mod p)] (mod m)

    As a requirement for using CMS you must provide an implicit CMSHasher[K] for the type K of the items you want to count. Algebird ships with several such implicits for commonly used types K such as Long and BigInt.

    If your type K is not supported out of the box, you have two options: 1) You provide a "translation" function to convert items of your (unsupported) type K to a supported type such as Double, and then use the contramap function of CMSHasher to create the required CMSHasher[K] for your type (see the documentation of contramap for an example); 2) You implement a CMSHasher[K] from scratch, using the existing CMSHasher implementations as a starting point.

  50. trait CMSHeavyHitters[K] extends AnyRef

    A trait for CMS implementations that can track heavy hitters in a data stream.

    A trait for CMS implementations that can track heavy hitters in a data stream.

    It is up to the implementation how the semantics of tracking heavy hitters are defined. For instance, one implementation could track the "top %" heavy hitters whereas another implementation could track the "top N" heavy hitters.

    Known implementations: TopCMS.

    K

    The type used to identify the elements to be counted.

  51. case class CMSInstance[K](countsTable: CountsTable[K], totalCount: Long, params: CMSParams[K]) extends CMS[K] with Product with Serializable

    The general Count-Min sketch structure, used for holding any number of elements.

  52. case class CMSItem[K](item: K, totalCount: Long, params: CMSParams[K]) extends CMS[K] with Product with Serializable

    Used for holding a single element, to avoid repeatedly adding elements from sparse counts tables.

  53. class CMSMonoid[K] extends Monoid[CMS[K]] with CommutativeMonoid[CMS[K]]

    Monoid for adding CMS sketches.

    Monoid for adding CMS sketches.

    Usage

    eps and delta are parameters that bound the error of each query estimate. For example, errors in answering point queries (e.g., how often has element x appeared in the stream described by the sketch?) are often of the form: "with probability p >= 1 - delta, the estimate is close to the truth by some factor depending on eps."

    The type K is the type of items you want to count. You must provide an implicit CMSHasher[K] for K, and Algebird ships with several such implicits for commonly used types such as Long and BigInt.

    If your type K is not supported out of the box, you have two options: 1) You provide a "translation" function to convert items of your (unsupported) type K to a supported type such as Double, and then use the contramap function of CMSHasher to create the required CMSHasher[K] for your type (see the documentation of CMSHasher for an example); 2) You implement a CMSHasher[K] from scratch, using the existing CMSHasher implementations as a starting point.

    Note: Because Arrays in Scala/Java not have sane equals and hashCode implementations, you cannot safely use types such as Array[Byte]. Extra work is required for Arrays. For example, you may opt to convert Array[T] to a Seq[T] via toSeq, or you can provide appropriate wrapper classes. Algebird provides one such wrapper class, Bytes, to safely wrap an Array[Byte] for use with CMS.

    K

    The type used to identify the elements to be counted. For example, if you want to count the occurrence of user names, you could map each username to a unique numeric ID expressed as a Long, and then count the occurrences of those Longs with a CMS of type K=Long. Note that this mapping between the elements of your problem domain and their identifiers used for counting via CMS should be bijective. We require a CMSHasher context bound for K, see CMSHasherImplicits for available implicits that can be imported. Which type K should you pick in practice? For domains that have less than 2^64 unique elements, you'd typically use Long. For larger domains you can try BigInt, for example. Other possibilities include Spire's SafeLong and Numerical data types (https://github.com/non/spire), though Algebird does not include the required implicits for CMS-hashing (cf. CMSHasherImplicits.

  54. case class CMSParams[K](hashes: Seq[CMSHash[K]], eps: Double, delta: Double, maxExactCountOpt: Option[Int] = None) extends Product with Serializable

    Configuration parameters for CMS.

    Configuration parameters for CMS.

    K

    The type used to identify the elements to be counted.

    hashes

    Pair-wise independent hashes functions. We need N=depth such functions (depth can be derived from delta).

    eps

    One-sided error bound on the error of each point query, i.e. frequency estimate.

    delta

    A bound on the probability that a query estimate does not lie within some small interval (an interval that depends on eps) around the truth.

    maxExactCountOpt

    An Option parameter about how many exact counts a sparse CMS wants to keep.

  55. class CMSSummation[K] extends AnyRef

    This mutable builder can be used when speed is essential and you can be sure the scope of the mutability cannot escape in an unsafe way.

    This mutable builder can be used when speed is essential and you can be sure the scope of the mutability cannot escape in an unsafe way. The intended use is to allocate and call result in one method without letting a reference to the instance escape into a closure.

  56. case class CMSZero[K](params: CMSParams[K]) extends CMS[K] with Product with Serializable

    Zero element.

    Zero element. Used for initialization.

  57. class CassandraMurmurHash extends AnyRef

    This is a very fast, non-cryptographic hash suitable for general hash-based lookup.

    This is a very fast, non-cryptographic hash suitable for general hash-based lookup. See http://murmurhash.googlepages.com/ for more details.

    hash32() and hash64() are MurmurHash 2.0. hash3_x64_128() is MurmurHash 3.0.

    The C version of MurmurHash 2.0 found at that site was ported to Java by Andrzej Bialecki (ab at getopt org).

  58. class ConstantGroup[T] extends Group[T]
  59. class ConstantRing[T] extends ConstantGroup[T] with Ring[T]
  60. case class Correlation(c2: Double, m2x: Double, m2y: Double, m1x: Double, m1y: Double, m0: Double) extends Product with Serializable

    A class to calculate covariance and the first two central moments of a sequence of pairs of Doubles, from which the pearson correlation coeifficient can be calculated.

    A class to calculate covariance and the first two central moments of a sequence of pairs of Doubles, from which the pearson correlation coeifficient can be calculated.

    m{i}x denotes the ith central moment of the first projection of the pair. m{i}y denotes the ith central moment of the second projection of the pair. c2 the covariance equivalent of the second central moment, i.e. c2 = Sum_(x,y) (x - m1x)*(y - m1y).

  61. case class DecayedValue(value: Double, scaledTime: Double) extends Ordered[DecayedValue] with Product with Serializable
  62. case class DecayedValueMonoid(eps: Double) extends Monoid[DecayedValue] with Product with Serializable
  63. case class DecayedVector[C[_]](vector: C[Double], scaledTime: Double) extends Product with Serializable
  64. final class DecayingCMS[K] extends Serializable

    DecayingCMS is a module to build count-min sketch instances whose counts decay exponentially.

    DecayingCMS is a module to build count-min sketch instances whose counts decay exponentially.

    Similar to a Map[K, com.twitter.algebird.DecayedValue], each key is associated with a single count value that decays over time. Unlike a map, the decyaing CMS is an approximate count -- in exchange for the possibility of over-counting, we can bound its size in memory.

    The intended use case is for metrics or machine learning where exact values aren't needed.

    You can expect the keys with the biggest values to be fairly accurate but the very small values (rare keys or very old keys) to be lost in the noise. For both metrics and ML this should be fine: you can't learn too much from very rare values.

    We recommend depth of at least 5, and width of at least 100, but you should do some experiments to determine the smallest parameters that will work for your use case.

  65. case class DenseHLL(bits: Int, v: Bytes) extends HLL with Product with Serializable

    These are the individual instances which the Monoid knows how to add

  66. case class DenseVector[V](iseq: Vector[V], sparseValue: V, denseCount: Int) extends AdaptiveVector[V] with Product with Serializable
  67. class EitherMonoid[L, R] extends EitherSemigroup[L, R] with Monoid[Either[L, R]]
  68. class EitherSemigroup[L, R] extends Semigroup[Either[L, R]]

    Either semigroup is useful for error handling.

    Either semigroup is useful for error handling. if everything is correct, use Right (it's right, get it?), if something goes wrong, use Left. plus does the normal thing for plus(Right, Right), or plus(Left, Left), but if exactly one is Left, we return that value (to keep the error condition). Typically, the left value will be a string representing the errors.

  69. case class Empty[T]() extends Interval[T] with Product with Serializable
  70. trait EventuallyAggregator[A, E, O, C] extends AbstractEventuallyAggregator[A, E, O, C]
  71. class EventuallyGroup[E, O] extends EventuallyMonoid[E, O] with Group[Either[E, O]]

    See also

    EventuallySemigroup

  72. class EventuallyMonoid[E, O] extends EventuallySemigroup[E, O] with Monoid[Either[E, O]]

    See also

    EventuallySemigroup

  73. trait EventuallyMonoidAggregator[A, E, O, C] extends AbstractEventuallyAggregator[A, E, O, C] with MonoidAggregator[A, Either[E, O], C]
  74. class EventuallyRing[E, O] extends EventuallyGroup[E, O] with Ring[Either[E, O]]

    See also

    EventuallySemigroup

  75. class EventuallySemigroup[E, O] extends Semigroup[Either[E, O]]

    Classes that support algebraic structures with dynamic switching between two representations, the original type O and the eventual type E.

    Classes that support algebraic structures with dynamic switching between two representations, the original type O and the eventual type E. In the case of Semigroup, we specify - Two Semigroups eventualSemigroup and originalSemigroup - A Semigroup homomorphism convert: O => E - A conditional mustConvert: O => Boolean Then we get a Semigroup[Either[E,O]], where: Left(x) + Left(y) = Left(x+y) Left(x) + Right(y) = Left(x+convert(y)) Right(x) + Left(y) = Left(convert(x)+y) Right(x) + Right(y) = Left(convert(x+y)) if mustConvert(x+y) Right(x+y) otherwise. EventuallyMonoid, EventuallyGroup, and EventuallyRing are defined analogously, with the contract that convert respect the appropriate structure.

  76. case class ExclusiveLower[T](lower: T) extends Interval[T] with Lower[T] with Product with Serializable
  77. case class ExclusiveUpper[T](upper: T) extends Interval[T] with Upper[T] with Product with Serializable
  78. case class ExpHist(conf: Config, buckets: Vector[Bucket], total: Long, time: Timestamp) extends Product with Serializable

    Exponential Histogram algorithm from http://www-cs-students.stanford.edu/~datar/papers/sicomp_streams.pdf

    Exponential Histogram algorithm from http://www-cs-students.stanford.edu/~datar/papers/sicomp_streams.pdf

    An Exponential Histogram is a sliding window counter that can guarantee a bounded relative error. You configure the data structure with

    - epsilon, the relative error you're willing to tolerate - windowSize, the number of time ticks that you want to track

    You interact with the data structure by adding (number, timestamp) pairs into the exponential histogram. querying it for an approximate counts with guess.

    The approximate count is guaranteed to be within conf.epsilon relative error of the true count seen across the supplied windowSize.

    Next steps:

    - efficient serialization - Query EH with a shorter window than the configured window - Discussion of epsilon vs memory tradeoffs

    conf

    the config values for this instance.

    buckets

    Vector of timestamps of each (powers of 2) ticks. This is the key to the exponential histogram representation. See ExpHist.Canonical for more info.

    total

    total ticks tracked. total == buckets.map(_.size).sum

    time

    current timestamp of this instance.

  79. type Field[V] = algebra.ring.Field[V]

    To keep code using algebird.Field compiling, we export algebra Field

  80. case class First[+T](get: T) extends Product with Serializable

    Tracks the "least recent", or earliest, wrapped instance of T by the order in which items are seen.

    Tracks the "least recent", or earliest, wrapped instance of T by the order in which items are seen.

    get

    wrapped instance of T

  81. case class FirstAggregator[T]() extends Aggregator[T, T, T] with Product with Serializable

    Aggregator that selects the first instance of T in the aggregated stream.

  82. trait FlatMapPreparer[A, T] extends Preparer[A, T]

    A Preparer that has had one or more flatMap operations applied.

    A Preparer that has had one or more flatMap operations applied. It can only accept MonoidAggregators.

  83. sealed trait Fold[-I, +O] extends Serializable

    Folds are first-class representations of "Traversable.foldLeft." They have the nice property that they can be fused to work in parallel over an input sequence.

    Folds are first-class representations of "Traversable.foldLeft." They have the nice property that they can be fused to work in parallel over an input sequence.

    A Fold accumulates inputs (I) into some internal type (X), converting to a defined output type (O) when done. We use existential types to hide internal details and to allow for internal and external (X and O) types to differ for "map" and "join."

    In discussing this type we draw parallels to Function1 and related types. You can think of a fold as a function "Seq[I] => O" but in reality we do not have to materialize the input sequence at once to "run" the fold.

    The traversal of the input data structure is NOT done by Fold itself. Instead we expose some methods like "overTraversable" that know how to iterate through various sequence types and drive the fold. We also expose some internal state so library authors can fold over their own types.

    See the companion object for constructors.

  84. class FoldApplicative[I] extends Applicative[[β$1$]Fold[I, β$1$]]

    Folds are Applicatives!

  85. final class FoldState[X, -I, +O] extends Serializable

    A FoldState defines a left fold with a "hidden" accumulator type.

    A FoldState defines a left fold with a "hidden" accumulator type. It is exposed so library authors can run Folds over their own sequence types.

    The fold can be executed correctly according to the properties of "add" and your traversed data structure. For example, the "add" function of a monoidal fold will be associative. A FoldState is valid for only one iteration because the accumulator (seeded by "start" may be mutable.

    The three components of a fold are add: (X, I) => X - updates and returns internal state for every input I start: X - the initial state end: X => O - transforms internal state to a final result

    Folding over Seq(x, y) would produce the result end(add(add(start, x), y))

  86. class FromAlgebraGroup[T] extends FromAlgebraMonoid[T] with Group[T]
  87. class FromAlgebraMonoid[T] extends FromAlgebraSemigroup[T] with Monoid[T]
  88. class FromAlgebraRing[T] extends Ring[T]
  89. class FromAlgebraSemigroup[T] extends Semigroup[T]
  90. class Function1Monoid[T] extends Monoid[(T) => T]

    Function1 monoid.

    Function1 monoid. plus means function composition, zero is the identity function

  91. trait Functor[M[_]] extends AnyRef

    Simple implementation of a Functor type-class.

    Simple implementation of a Functor type-class.

    Laws Functors must follow: map(m)(id) == m map(m)(f andThen g) == map(map(m)(f))(g)

    Annotations
    @implicitNotFound()
  92. class FunctorOperators[A, M[_]] extends AnyRef

    This enrichment allows us to use our Functor instances in for expressions: if (import Functor._) has been done

  93. case class GenHLLAggregator[K](hllMonoid: HyperLogLogMonoid, hash: Hash128[K]) extends MonoidAggregator[K, HLL, HLL] with Product with Serializable
  94. trait GeneratedGroupImplicits extends AnyRef
  95. trait GeneratedMonoidImplicits extends AnyRef
  96. trait GeneratedRingImplicits extends AnyRef
  97. trait GeneratedSemigroupImplicits extends AnyRef
  98. trait GeneratedTupleAggregator extends AnyRef
  99. abstract class GenericMapMonoid[K, V, M <: Map[K, V]] extends Monoid[M] with MapOperations[K, V, M]
  100. trait GenericMapRing[K, V, M <: Map[K, V]] extends Rng[M] with MapOperations[K, V, M]

    You can think of this as a Sparse vector ring

  101. trait Group[T] extends algebra.Group[T] with Monoid[T] with AdditiveGroup[T]

    Group: this is a monoid that also has subtraction (and negation): So, you can do (a-b), or -a (which is equal to 0 - a).

    Group: this is a monoid that also has subtraction (and negation): So, you can do (a-b), or -a (which is equal to 0 - a).

    Annotations
    @implicitNotFound()
  102. sealed abstract class HLL extends Serializable
  103. case class HLLSeries(bits: Int, rows: Vector[Map[Int, Long]]) extends Product with Serializable

    HLLSeries can produce a HyperLogLog counter for any window into the past, using a constant factor more space than HyperLogLog.

    HLLSeries can produce a HyperLogLog counter for any window into the past, using a constant factor more space than HyperLogLog.

    For each hash bucket, rather than keeping a single max RhoW value, it keeps every RhoW value it has seen, and the max timestamp where it saw that value. This allows it to reconstruct an HLL as it would be had it started at zero at any given point in the past, and seen the same updates this structure has seen.

    bits

    The number of bits to use

    rows

    Vector of maps of RhoW -> max timestamp where it was seen

    returns

    New HLLSeries

  104. trait Hash128[-K] extends Serializable

    A typeclass to represent hashing to 128 bits.

    A typeclass to represent hashing to 128 bits. Used for HLL, but possibly other applications

  105. class HashingTrickMonoid[V] extends Monoid[AdaptiveVector[V]]
  106. case class HeavyHitter[K](item: K, count: Long) extends Serializable with Product
  107. case class HeavyHitters[K](hhs: Set[HeavyHitter[K]]) extends Serializable with Product

    Containers for holding heavy hitter items and their associated counts.

  108. abstract class HeavyHittersLogic[K] extends Serializable

    Controls how a CMS that implements CMSHeavyHitters tracks heavy hitters.

  109. case class HyperLogLogAggregator(hllMonoid: HyperLogLogMonoid) extends MonoidAggregator[Array[Byte], HLL, HLL] with Product with Serializable
  110. class HyperLogLogMonoid extends Monoid[HLL] with BoundedSemilattice[HLL]
  111. class HyperLogLogSeriesMonoid extends Monoid[HLLSeries]

    val hllSeriesMonoid = new HyperLogLogSeriesMonoid(bits)

    Example Usage

    val hllSeriesMonoid = new HyperLogLogSeriesMonoid(bits)

    val examples: Seq[Array[Byte], Long] val series = examples .map { case (bytes, timestamp) => hllSeriesMonoid.create(bytes, timestamp) } .reduce { hllSeriesMonoid.plus(_,_) }

    val estimate1 = series.since(timestamp1.toLong).toHLL.estimatedSize val estimate2 = series.since(timestamp2.toLong).toHLL.estimatedSize

  112. case class Identity[T](get: T) extends Product with Serializable
  113. sealed trait Implicits extends LowPrioImpicits
  114. case class InclusiveLower[T](lower: T) extends Interval[T] with Lower[T] with Product with Serializable
  115. case class InclusiveUpper[T](upper: T) extends Interval[T] with Upper[T] with Product with Serializable
  116. class IndexedSeqGroup[T] extends IndexedSeqMonoid[T] with Group[IndexedSeq[T]]
  117. class IndexedSeqMonoid[T] extends IndexedSeqSemigroup[T] with Monoid[IndexedSeq[T]]
  118. class IndexedSeqRing[T] extends IndexedSeqGroup[T] with Ring[IndexedSeq[T]]
  119. class IndexedSeqSemigroup[T] extends Semigroup[IndexedSeq[T]]

    Note that this works similar to Semigroup[Map[Int,T]] not like Semigroup[List[T]] This does element-wise operations, like standard vector math, not concatenation, like Semigroup[String] or Semigroup[List[T]]

    Note that this works similar to Semigroup[Map[Int,T]] not like Semigroup[List[T]] This does element-wise operations, like standard vector math, not concatenation, like Semigroup[String] or Semigroup[List[T]]

    If l.size != r.size, then only sums the elements up to the index min(l.size, r.size); appends the remainder to the result.

  120. class IntegralPredecessible[T] extends Predecessible[T]
  121. class IntegralSuccessible[T] extends Successible[T]
  122. case class Intersection[L[t] <: Lower[t], U[t] <: Upper[t], T](lower: L[T], upper: U[T]) extends Interval[T] with Product with Serializable
  123. sealed trait Interval[T] extends Serializable

    Represents a single interval on a T with an Ordering

  124. class InvariantGroup[T, U] extends InvariantMonoid[T, U] with Group[U]
  125. class InvariantMonoid[T, U] extends InvariantSemigroup[T, U] with Monoid[U]
  126. class InvariantRing[T, U] extends InvariantGroup[T, U] with Ring[U]
  127. class InvariantSemigroup[T, U] extends Semigroup[U]
  128. class JListMonoid[T] extends Monoid[List[T]]

    Since Lists are mutable, this always makes a full copy.

    Since Lists are mutable, this always makes a full copy. Prefer scala immutable Lists if you use scala immutable lists, the tail of the result of plus is always the right argument

  129. class JMapMonoid[K, V] extends Monoid[Map[K, V]]

    Since maps are mutable, this always makes a full copy.

    Since maps are mutable, this always makes a full copy. Prefer scala immutable maps if you use scala immutable maps, this operation is much faster TODO extend this to Group, Ring

  130. case class Last[+T](get: T) extends Product with Serializable

    Tracks the "most recent", or last, wrapped instance of T by the order in which items are seen.

    Tracks the "most recent", or last, wrapped instance of T by the order in which items are seen.

    get

    wrapped instance of T

  131. case class LastAggregator[T]() extends Aggregator[T, T, T] with Product with Serializable

    Aggregator that selects the last instance of T in the aggregated stream.

  132. class ListMonoid[T] extends Monoid[List[T]]

    List concatenation monoid.

    List concatenation monoid. plus means concatenation, zero is empty list

  133. sealed trait LowPrioImpicits extends AnyRef
  134. sealed trait Lower[T] extends Interval[T]
  135. trait MapAggregator[A, B, K, C] extends Aggregator[A, B, Map[K, C]]
  136. class MapGroup[K, V] extends MapMonoid[K, V] with Group[Map[K, V]]

    You can think of this as a Sparse vector group

  137. class MapMonoid[K, V] extends GenericMapMonoid[K, V, Map[K, V]]
  138. trait MapMonoidAggregator[A, B, K, C] extends MonoidAggregator[A, B, Map[K, C]]
  139. trait MapOperations[K, V, M <: Map[K, V]] extends AnyRef
  140. trait MapPreparer[A, T] extends Preparer[A, T]

    A Preparer that has had zero or more map transformations applied, but no flatMaps.

    A Preparer that has had zero or more map transformations applied, but no flatMaps. This can produce any type of Aggregator.

  141. class MapRing[K, V] extends MapGroup[K, V] with GenericMapRing[K, V, Map[K, V]]
  142. case class Max[+T](get: T) extends Product with Serializable

    Tracks the maximum wrapped instance of some ordered type T.

    Tracks the maximum wrapped instance of some ordered type T.

    Max[T] is a Semigroup for all types T. If T has some minimum element (Long has Long.MinValue, for example), then Max[T] is a Monoid.

    get

    wrapped instance of T

  143. case class MaxAggregator[T]()(implicit ord: Ordering[T]) extends Aggregator[T, T, T] with Product with Serializable

    Aggregator that selects the maximum instance of T in the aggregated stream.

  144. trait Metric[-V] extends Serializable
    Annotations
    @implicitNotFound()
  145. case class Min[+T](get: T) extends Product with Serializable

    Tracks the minimum wrapped instance of some ordered type T.

    Tracks the minimum wrapped instance of some ordered type T.

    Min[T] is a Semigroup for all types T. If T has some maximum element (Long has Long.MaxValue, for example), then Min[T] is a Monoid.

    get

    wrapped instance of T

  146. case class MinAggregator[T]()(implicit ord: Ordering[T]) extends Aggregator[T, T, T] with Product with Serializable

    Aggregator that selects the minimum instance of T in the aggregated stream.

  147. final case class MinHashSignature(bytes: Array[Byte]) extends AnyVal with Product with Serializable

    MinHasher as a Monoid operates on this class to avoid the too generic Array[Byte].

    MinHasher as a Monoid operates on this class to avoid the too generic Array[Byte]. The bytes are assumed to be never modified. The only reason we did not use IndexedSeq[Byte] instead of Array[Byte] is because a ByteBuffer is used internally in MinHasher and it can wrap Array[Byte].

  148. abstract class MinHasher[H] extends Monoid[MinHashSignature]

    Instances of MinHasher can create, combine, and compare fixed-sized signatures of arbitrarily sized sets.

    Instances of MinHasher can create, combine, and compare fixed-sized signatures of arbitrarily sized sets.

    A signature is represented by a byte array of approx maxBytes size. You can initialize a signature with a single element, usually a Long or String. You can combine any two set's signatures to produce the signature of their union. You can compare any two set's signatures to estimate their Jaccard similarity. You can use a set's signature to estimate the number of distinct values in the set. You can also use a combination of the above to estimate the size of the intersection of two sets from their signatures. The more bytes in the signature, the more accurate all of the above will be.

    You can also use these signatures to quickly find similar sets without doing n^2 comparisons. Each signature is assigned to several buckets; sets whose signatures end up in the same bucket are likely to be similar. The targetThreshold controls the desired level of similarity - the higher the threshold, the more efficiently you can find all the similar sets.

    This abstract superclass is generic with regards to the size of the hash used. Depending on the number of unique values in the domain of the sets, you may want a MinHasher16, a MinHasher32, or a new custom subclass.

    This implementation is modeled after Chapter 3 of Ullman and Rajaraman's Mining of Massive Datasets: http://infolab.stanford.edu/~ullman/mmds/ch3a.pdf

  149. class MinHasher16 extends MinHasher[Char]
  150. class MinHasher32 extends MinHasher[Int]
  151. sealed trait MinPlus[+V] extends Serializable
  152. class MinPlusSemiring[V] extends Rig[MinPlus[V]]
  153. final case class MinPlusValue[V](get: V) extends AnyVal with MinPlus[V] with Product with Serializable
  154. sealed class Moments extends Product with Serializable

    A class to calculate the first five central moments over a sequence of Doubles.

    A class to calculate the first five central moments over a sequence of Doubles. Given the first five central moments, we can then calculate metrics like skewness and kurtosis.

    m{i} denotes the ith central moment.

    This code manually inlines code to make it look like a case class. This is done because we changed the count from a Long to a Double to enable the scale method, which allows exponential decays of moments, but we didn't want to break backwards binary compatibility.

  155. class MomentsMonoid extends Monoid[Moments] with CommutativeMonoid[Moments]
  156. trait Monad[M[_]] extends Applicative[M]

    Simple implementation of a Monad type-class.

    Simple implementation of a Monad type-class. Subclasses only need to override apply and flatMap, but they should override map, join, joinWith, and sequence if there are better implementations.

    Laws Monads must follow: identities: flatMap(apply(x))(fn) == fn(x) flatMap(m)(apply _) == m associativity on flatMap (you can either flatMap f first, or f to g: flatMap(flatMap(m)(f))(g) == flatMap(m) { x => flatMap(f(x))(g) }

    Annotations
    @implicitNotFound()
  157. class MonadOperators[A, M[_]] extends ApplicativeOperators[A, M]

    This enrichment allows us to use our Monad instances in for expressions: if (import Monad._) has been done

  158. trait Monoid[T] extends Semigroup[T] with algebra.Monoid[T] with AdditiveMonoid[T]

    Monoid (take a deep breath, and relax about the weird name): This is a semigroup that has an additive identity (called zero), such that a+0=a, 0+a=a, for every a

    Monoid (take a deep breath, and relax about the weird name): This is a semigroup that has an additive identity (called zero), such that a+0=a, 0+a=a, for every a

    Annotations
    @implicitNotFound()
  159. trait MonoidAggregator[-A, B, +C] extends Aggregator[A, B, C]
  160. class MonoidCombinator[A, B] extends SemigroupCombinator[A, B] with Monoid[(A, B)]
  161. final case class MurmurHash128(seed: Long) extends AnyVal with Product with Serializable
  162. class NumericRing[T] extends Ring[T]
  163. trait NumericRingProvider extends AnyRef
  164. class OptionGroup[T] extends OptionMonoid[T] with Group[Option[T]]

    Some(5) - Some(3) == Some(2) Some(5) - Some(5) == None negate Some(5) == Some(-5) Note: Some(0) and None are equivalent under this Group

  165. class OptionMonoid[T] extends Monoid[Option[T]]

    Some(5) + Some(3) == Some(8) Some(5) + None == Some(5)

  166. final case class OrVal(get: Boolean) extends AnyVal with Product with Serializable
  167. trait Predecessible[T] extends Serializable

    This is a typeclass to represent things which are countable down.

    This is a typeclass to represent things which are countable down. Note that it is important that a value prev(t) is always less than t. Note that prev returns Option because this class comes with the notion that some items may reach a minimum key, which is None.

  168. sealed trait Preparer[A, T] extends Serializable

    Preparer is a way to build up an Aggregator through composition using a more natural API: it allows you to start with the input type and describe a series of transformations and aggregations from there, rather than starting from the aggregation and composing "outwards" in both directions.

    Preparer is a way to build up an Aggregator through composition using a more natural API: it allows you to start with the input type and describe a series of transformations and aggregations from there, rather than starting from the aggregation and composing "outwards" in both directions.

    Uses of Preparer will always start with a call to Preparer[A], and end with a call to monoidAggregate or a related method, to produce an Aggregator instance.

  169. sealed trait Priority[+P, +F] extends AnyRef

    Priority is a type class for prioritized implicit search.

    Priority is a type class for prioritized implicit search.

    This type class will attempt to provide an implicit instance of P (the preferred type). If that type is not available it will fallback to F (the fallback type). If neither type is available then a Priority[P, F] instance will not be available.

    This type can be useful for problems where multiple algorithms can be used, depending on the type classes available.

    taken from non/algebra until we make algebird depend on non/algebra

  170. class Product10Group[X, A, B, C, D, E, F, G, H, I, J] extends Product10Monoid[X, A, B, C, D, E, F, G, H, I, J] with Group[X]

    Combine 10 groups into a product group

  171. class Product10Monoid[X, A, B, C, D, E, F, G, H, I, J] extends Product10Semigroup[X, A, B, C, D, E, F, G, H, I, J] with Monoid[X]

    Combine 10 monoids into a product monoid

  172. class Product10Ring[X, A, B, C, D, E, F, G, H, I, J] extends Product10Group[X, A, B, C, D, E, F, G, H, I, J] with Ring[X]

    Combine 10 rings into a product ring

  173. class Product10Semigroup[X, A, B, C, D, E, F, G, H, I, J] extends Semigroup[X]

    Combine 10 semigroups into a product semigroup

  174. class Product11Group[X, A, B, C, D, E, F, G, H, I, J, K] extends Product11Monoid[X, A, B, C, D, E, F, G, H, I, J, K] with Group[X]

    Combine 11 groups into a product group

  175. class Product11Monoid[X, A, B, C, D, E, F, G, H, I, J, K] extends Product11Semigroup[X, A, B, C, D, E, F, G, H, I, J, K] with Monoid[X]

    Combine 11 monoids into a product monoid

  176. class Product11Ring[X, A, B, C, D, E, F, G, H, I, J, K] extends Product11Group[X, A, B, C, D, E, F, G, H, I, J, K] with Ring[X]

    Combine 11 rings into a product ring

  177. class Product11Semigroup[X, A, B, C, D, E, F, G, H, I, J, K] extends Semigroup[X]

    Combine 11 semigroups into a product semigroup

  178. class Product12Group[X, A, B, C, D, E, F, G, H, I, J, K, L] extends Product12Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L] with Group[X]

    Combine 12 groups into a product group

  179. class Product12Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L] extends Product12Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L] with Monoid[X]

    Combine 12 monoids into a product monoid

  180. class Product12Ring[X, A, B, C, D, E, F, G, H, I, J, K, L] extends Product12Group[X, A, B, C, D, E, F, G, H, I, J, K, L] with Ring[X]

    Combine 12 rings into a product ring

  181. class Product12Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L] extends Semigroup[X]

    Combine 12 semigroups into a product semigroup

  182. class Product13Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M] extends Product13Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M] with Group[X]

    Combine 13 groups into a product group

  183. class Product13Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M] extends Product13Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M] with Monoid[X]

    Combine 13 monoids into a product monoid

  184. class Product13Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M] extends Product13Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M] with Ring[X]

    Combine 13 rings into a product ring

  185. class Product13Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M] extends Semigroup[X]

    Combine 13 semigroups into a product semigroup

  186. class Product14Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Product14Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N] with Group[X]

    Combine 14 groups into a product group

  187. class Product14Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Product14Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N] with Monoid[X]

    Combine 14 monoids into a product monoid

  188. class Product14Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Product14Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N] with Ring[X]

    Combine 14 rings into a product ring

  189. class Product14Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Semigroup[X]

    Combine 14 semigroups into a product semigroup

  190. class Product15Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Product15Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] with Group[X]

    Combine 15 groups into a product group

  191. class Product15Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Product15Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] with Monoid[X]

    Combine 15 monoids into a product monoid

  192. class Product15Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Product15Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] with Ring[X]

    Combine 15 rings into a product ring

  193. class Product15Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Semigroup[X]

    Combine 15 semigroups into a product semigroup

  194. class Product16Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Product16Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] with Group[X]

    Combine 16 groups into a product group

  195. class Product16Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Product16Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] with Monoid[X]

    Combine 16 monoids into a product monoid

  196. class Product16Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Product16Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] with Ring[X]

    Combine 16 rings into a product ring

  197. class Product16Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Semigroup[X]

    Combine 16 semigroups into a product semigroup

  198. class Product17Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Product17Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] with Group[X]

    Combine 17 groups into a product group

  199. class Product17Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Product17Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] with Monoid[X]

    Combine 17 monoids into a product monoid

  200. class Product17Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Product17Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] with Ring[X]

    Combine 17 rings into a product ring

  201. class Product17Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Semigroup[X]

    Combine 17 semigroups into a product semigroup

  202. class Product18Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Product18Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] with Group[X]

    Combine 18 groups into a product group

  203. class Product18Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Product18Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] with Monoid[X]

    Combine 18 monoids into a product monoid

  204. class Product18Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Product18Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] with Ring[X]

    Combine 18 rings into a product ring

  205. class Product18Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Semigroup[X]

    Combine 18 semigroups into a product semigroup

  206. class Product19Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Product19Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] with Group[X]

    Combine 19 groups into a product group

  207. class Product19Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Product19Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] with Monoid[X]

    Combine 19 monoids into a product monoid

  208. class Product19Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Product19Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] with Ring[X]

    Combine 19 rings into a product ring

  209. class Product19Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Semigroup[X]

    Combine 19 semigroups into a product semigroup

  210. class Product20Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Product20Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] with Group[X]

    Combine 20 groups into a product group

  211. class Product20Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Product20Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] with Monoid[X]

    Combine 20 monoids into a product monoid

  212. class Product20Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Product20Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] with Ring[X]

    Combine 20 rings into a product ring

  213. class Product20Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Semigroup[X]

    Combine 20 semigroups into a product semigroup

  214. class Product21Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Product21Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] with Group[X]

    Combine 21 groups into a product group

  215. class Product21Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Product21Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] with Monoid[X]

    Combine 21 monoids into a product monoid

  216. class Product21Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Product21Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] with Ring[X]

    Combine 21 rings into a product ring

  217. class Product21Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Semigroup[X]

    Combine 21 semigroups into a product semigroup

  218. class Product22Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Product22Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] with Group[X]

    Combine 22 groups into a product group

  219. class Product22Monoid[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Product22Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] with Monoid[X]

    Combine 22 monoids into a product monoid

  220. class Product22Ring[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Product22Group[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] with Ring[X]

    Combine 22 rings into a product ring

  221. class Product22Semigroup[X, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Semigroup[X]

    Combine 22 semigroups into a product semigroup

  222. class Product2Group[X, A, B] extends Product2Monoid[X, A, B] with Group[X]

    Combine 2 groups into a product group

  223. class Product2Monoid[X, A, B] extends Product2Semigroup[X, A, B] with Monoid[X]

    Combine 2 monoids into a product monoid

  224. class Product2Ring[X, A, B] extends Product2Group[X, A, B] with Ring[X]

    Combine 2 rings into a product ring

  225. class Product2Semigroup[X, A, B] extends Semigroup[X]

    Combine 2 semigroups into a product semigroup

  226. class Product3Group[X, A, B, C] extends Product3Monoid[X, A, B, C] with Group[X]

    Combine 3 groups into a product group

  227. class Product3Monoid[X, A, B, C] extends Product3Semigroup[X, A, B, C] with Monoid[X]

    Combine 3 monoids into a product monoid

  228. class Product3Ring[X, A, B, C] extends Product3Group[X, A, B, C] with Ring[X]

    Combine 3 rings into a product ring

  229. class Product3Semigroup[X, A, B, C] extends Semigroup[X]

    Combine 3 semigroups into a product semigroup

  230. class Product4Group[X, A, B, C, D] extends Product4Monoid[X, A, B, C, D] with Group[X]

    Combine 4 groups into a product group

  231. class Product4Monoid[X, A, B, C, D] extends Product4Semigroup[X, A, B, C, D] with Monoid[X]

    Combine 4 monoids into a product monoid

  232. class Product4Ring[X, A, B, C, D] extends Product4Group[X, A, B, C, D] with Ring[X]

    Combine 4 rings into a product ring

  233. class Product4Semigroup[X, A, B, C, D] extends Semigroup[X]

    Combine 4 semigroups into a product semigroup

  234. class Product5Group[X, A, B, C, D, E] extends Product5Monoid[X, A, B, C, D, E] with Group[X]

    Combine 5 groups into a product group

  235. class Product5Monoid[X, A, B, C, D, E] extends Product5Semigroup[X, A, B, C, D, E] with Monoid[X]

    Combine 5 monoids into a product monoid

  236. class Product5Ring[X, A, B, C, D, E] extends Product5Group[X, A, B, C, D, E] with Ring[X]

    Combine 5 rings into a product ring

  237. class Product5Semigroup[X, A, B, C, D, E] extends Semigroup[X]

    Combine 5 semigroups into a product semigroup

  238. class Product6Group[X, A, B, C, D, E, F] extends Product6Monoid[X, A, B, C, D, E, F] with Group[X]

    Combine 6 groups into a product group

  239. class Product6Monoid[X, A, B, C, D, E, F] extends Product6Semigroup[X, A, B, C, D, E, F] with Monoid[X]

    Combine 6 monoids into a product monoid

  240. class Product6Ring[X, A, B, C, D, E, F] extends Product6Group[X, A, B, C, D, E, F] with Ring[X]

    Combine 6 rings into a product ring

  241. class Product6Semigroup[X, A, B, C, D, E, F] extends Semigroup[X]

    Combine 6 semigroups into a product semigroup

  242. class Product7Group[X, A, B, C, D, E, F, G] extends Product7Monoid[X, A, B, C, D, E, F, G] with Group[X]

    Combine 7 groups into a product group

  243. class Product7Monoid[X, A, B, C, D, E, F, G] extends Product7Semigroup[X, A, B, C, D, E, F, G] with Monoid[X]

    Combine 7 monoids into a product monoid

  244. class Product7Ring[X, A, B, C, D, E, F, G] extends Product7Group[X, A, B, C, D, E, F, G] with Ring[X]

    Combine 7 rings into a product ring

  245. class Product7Semigroup[X, A, B, C, D, E, F, G] extends Semigroup[X]

    Combine 7 semigroups into a product semigroup

  246. class Product8Group[X, A, B, C, D, E, F, G, H] extends Product8Monoid[X, A, B, C, D, E, F, G, H] with Group[X]

    Combine 8 groups into a product group

  247. class Product8Monoid[X, A, B, C, D, E, F, G, H] extends Product8Semigroup[X, A, B, C, D, E, F, G, H] with Monoid[X]

    Combine 8 monoids into a product monoid

  248. class Product8Ring[X, A, B, C, D, E, F, G, H] extends Product8Group[X, A, B, C, D, E, F, G, H] with Ring[X]

    Combine 8 rings into a product ring

  249. class Product8Semigroup[X, A, B, C, D, E, F, G, H] extends Semigroup[X]

    Combine 8 semigroups into a product semigroup

  250. class Product9Group[X, A, B, C, D, E, F, G, H, I] extends Product9Monoid[X, A, B, C, D, E, F, G, H, I] with Group[X]

    Combine 9 groups into a product group

  251. class Product9Monoid[X, A, B, C, D, E, F, G, H, I] extends Product9Semigroup[X, A, B, C, D, E, F, G, H, I] with Monoid[X]

    Combine 9 monoids into a product monoid

  252. class Product9Ring[X, A, B, C, D, E, F, G, H, I] extends Product9Group[X, A, B, C, D, E, F, G, H, I] with Ring[X]

    Combine 9 rings into a product ring

  253. class Product9Semigroup[X, A, B, C, D, E, F, G, H, I] extends Semigroup[X]

    Combine 9 semigroups into a product semigroup

  254. trait ProductGroups extends AnyRef
  255. trait ProductMonoids extends AnyRef
  256. trait ProductRings extends AnyRef
  257. trait ProductSemigroups extends AnyRef
  258. final class PureOp[A] extends AnyVal
  259. class QTree[A] extends Product6[Long, Int, Long, A, Option[QTree[A]], Option[QTree[A]]] with Serializable
  260. case class QTreeAggregator[T](percentile: Double, k: Int = QTreeAggregator.DefaultK)(implicit num: Numeric[T]) extends Aggregator[T, QTree[Unit], Intersection[InclusiveLower, InclusiveUpper, Double]] with QTreeAggregatorLike[T] with Product with Serializable

    QTree aggregator is an aggregator that can be used to find the approximate percentile bounds.

    QTree aggregator is an aggregator that can be used to find the approximate percentile bounds. The items that are iterated over to produce this approximation cannot be negative. Returns an Intersection which represents the bounded approximation.

  261. trait QTreeAggregatorLike[T] extends AnyRef
  262. case class QTreeAggregatorLowerBound[T](percentile: Double, k: Int = QTreeAggregator.DefaultK)(implicit num: Numeric[T]) extends Aggregator[T, QTree[Unit], Double] with QTreeAggregatorLike[T] with Product with Serializable

    QTreeAggregatorLowerBound is an aggregator that is used to find an appoximate percentile.

    QTreeAggregatorLowerBound is an aggregator that is used to find an appoximate percentile. This is similar to a QTreeAggregator, but is a convenience because instead of returning an Intersection, it instead returns the lower bound of the percentile. Like a QTreeAggregator, the items that are iterated over to produce this approximation cannot be negative.

  263. class QTreeSemigroup[A] extends Semigroup[QTree[A]]
  264. sealed trait ResetState[+A] extends AnyRef

    Used to represent cases where we need to periodically reset a + b = a + b

    Used to represent cases where we need to periodically reset a + b = a + b

    |a + b = |(a + b) a + |b = |b

    |a + |b = |b

  265. class ResetStateMonoid[A] extends Monoid[ResetState[A]]
  266. case class ResetValue[+A](get: A) extends ResetState[A] with Product with Serializable
  267. final class RichCBitSet extends AnyVal
  268. class RichTraversable[T] extends AnyRef
  269. sealed abstract class RightFolded[+In, +Out] extends AnyRef
  270. sealed abstract class RightFolded2[+In, +Out, +Acc] extends AnyRef
  271. class RightFolded2Monoid[In, Out, Acc] extends Monoid[RightFolded2[In, Out, Acc]]
  272. case class RightFoldedToFold[+In](in: List[In]) extends RightFolded[In, Nothing] with Product with Serializable
  273. case class RightFoldedToFold2[+In](in: List[In]) extends RightFolded2[In, Nothing, Nothing] with Product with Serializable
  274. case class RightFoldedValue[+Out](v: Out) extends RightFolded[Nothing, Out] with Product with Serializable
  275. case class RightFoldedValue2[+In, +Out, +Acc](v: Out, acc: Acc, rvals: List[In]) extends RightFolded2[In, Out, Acc] with Product with Serializable
  276. trait Ring[T] extends Group[T] with CommutativeGroup[T] with algebra.ring.Ring[T]

    Ring: Group + multiplication (see: http://en.wikipedia.org/wiki/Ring_%28mathematics%29) and the three elements it defines:

    Ring: Group + multiplication (see: http://en.wikipedia.org/wiki/Ring_%28mathematics%29) and the three elements it defines:

    • additive identity aka zero
    • addition
    • multiplication

    Note, if you have distributive property, additive inverses, and multiplicative identity you can prove you have a commutative group under the ring:

    1. (a + 1)*(b + 1) = a(b + 1) + (b + 1) 2. = ab + a + b + 1 3. or: 4. 5. = (a + 1)b + (a + 1) 6. = ab + b + a + 1 7. 8. So: ab + a + b + 1 == ab + b + a + 1 9. using the fact that -(ab) and -1 exist, we get: 10. a + b == b + a
    Annotations
    @implicitNotFound()
  277. trait RingAggregator[-A, B, +C] extends MonoidAggregator[A, B, C]
  278. sealed abstract class SGD[+Pos] extends AnyRef
  279. class SGDMonoid[Pos] extends Monoid[SGD[Pos]]

    Basically a specific implementation of the RightFoldedMonoid gradient is the gradient of the function to be minimized To use this, you need to insert an initial weight SGDWeights before you start adding SGDPos objects.

    Basically a specific implementation of the RightFoldedMonoid gradient is the gradient of the function to be minimized To use this, you need to insert an initial weight SGDWeights before you start adding SGDPos objects. Otherwise you will just be doing list concatenation.

  280. case class SGDPos[+Pos](pos: List[Pos]) extends SGD[Pos] with Product with Serializable
  281. case class SGDWeights(count: Long, weights: IndexedSeq[Double]) extends SGD[Nothing] with Product with Serializable
  282. case class SSMany[T] extends SpaceSaver[T] with Product with Serializable
  283. case class SSOne[T] extends SpaceSaver[T] with Product with Serializable
  284. class ScMapGroup[K, V] extends ScMapMonoid[K, V] with Group[Map[K, V]]
  285. class ScMapMonoid[K, V] extends GenericMapMonoid[K, V, Map[K, V]]
  286. class ScMapRing[K, V] extends ScMapGroup[K, V] with GenericMapRing[K, V, Map[K, V]]
  287. sealed abstract class Scan[-I, +O] extends Serializable

    The Scan trait is an alternative to the scanLeft method on iterators/other collections for a range of of use-cases where scanLeft is awkward to use.

    The Scan trait is an alternative to the scanLeft method on iterators/other collections for a range of of use-cases where scanLeft is awkward to use. At a high level it provides some of the same functionality as scanLeft, but with a separation of "what is the state of the scan" from "what are the elements that I'm scanning over?". In particular, when scanning over an iterator with N elements, the output is an iterator with N elements (in contrast to scanLeft's N+1).

    If you find yourself writing a scanLeft over pairs of elements, where you only use one element of the pair within the scanLeft, then throw that element away in a map immediately after the scanLeft is done, then this abstraction is for you.

    The canonical method to use a scan is apply.

    I

    The type of elements that the computation is scanning over.

    O

    The output type of the scan (typically distinct from the hidden State of the scan).

  288. class ScanApplicative[I] extends Applicative[[β$1$]Scan[I, β$1$]]
  289. class ScopedTopNCMSMonoid[K1, K2] extends TopCMSMonoid[(K1, K2)]
  290. case class ScopedTopNLogic[K1, K2](heavyHittersN: Int) extends HeavyHittersLogic[(K1, K2)] with Product with Serializable

    K1 defines a scope for the CMS.

    K1 defines a scope for the CMS. For each k1, keep the top heavyHittersN associated k2 values.

  291. trait Semigroup[T] extends algebra.Semigroup[T] with AdditiveSemigroup[T]

    A semigroup is any type T with an associative operation (plus):

    A semigroup is any type T with an associative operation (plus):

    a plus (b plus c) = (a plus b) plus c

    Example instances:

    • Semigroup[Int]: plus Int#+
    • Semigroup[List[T]]: plus is List#++
    Annotations
    @implicitNotFound()
  292. class SemigroupCombinator[A, B] extends Semigroup[(A, B)]

    This is a combinator on semigroups, after you do the plus, you transform B with a fold function This will not be valid for all fold functions.

    This is a combinator on semigroups, after you do the plus, you transform B with a fold function This will not be valid for all fold functions. You need to prove that it is still associative.

    Clearly only values of (a,b) are valid if fold(a,b) == b, so keep that in mind.

    I have not yet found a sufficient condition on (A,B) => B that makes it correct Clearly a (trivial) constant function {(l,r) => r} works. Also, if B is List[T], and (l:A,r:List[T]) = r.sortBy(fn(l)) this works as well (due to the associativity on A, and the fact that the list never loses data).

    For approximate lists (like top-K applications) this might work (or be close enough to associative that for approximation algorithms it is fine), and in fact, that is the main motivation of this code: Produce some ordering in A, and use it to do sorted-topK on the list in B.

    Seems like an open topic here.... you are obliged to think on your own about this.

  293. class SentinelCache[K, V] extends AnyRef

    This is a summing cache whose goal is to grow until we run out of memory, at which point it clears itself and stops growing.

    This is a summing cache whose goal is to grow until we run out of memory, at which point it clears itself and stops growing. Note that we can lose the values in this cache at any point; we don't put anything here we care about.

  294. class SeqMonoid[T] extends Monoid[Seq[T]]
  295. sealed abstract case class SetDiff[T] extends Product with Serializable

    SetDiff is a class that represents changes applied to a set.

    SetDiff is a class that represents changes applied to a set. It is in fact a Set[T] => Set[T], but doesn't extend Function1 since that brings in a pack of methods that we don't necessarily want.

  296. class SetMonoid[T] extends Monoid[Set[T]]

    Set union monoid.

    Set union monoid. plus means union, zero is empty set

  297. case class SetSizeAggregator[A](hllBits: Int, maxSetSize: Int = 10)(implicit toBytes: (A) => Array[Byte]) extends SetSizeAggregatorBase[A] with Product with Serializable
  298. abstract class SetSizeAggregatorBase[A] extends EventuallyMonoidAggregator[A, HLL, Set[A], Long]

    convert is not not implemented here

  299. case class SetSizeHashAggregator[A](hllBits: Int, maxSetSize: Int = 10)(implicit hash: Hash128[A]) extends SetSizeAggregatorBase[A] with Product with Serializable

    Use a Hash128 when converting to HLL, rather than an implicit conversion to Array[Byte] Unifying with SetSizeAggregator would be nice, but since they only differ in an implicit parameter, scala seems to be giving me errors.

  300. case class SetValue[+A](get: A) extends ResetState[A] with Product with Serializable
  301. case class SketchMap[K, V](valuesTable: AdaptiveMatrix[V], heavyHitterKeys: List[K], totalValue: V) extends Serializable with Product
  302. case class SketchMapAggregator[K, V](params: SketchMapParams[K], skmMonoid: SketchMapMonoid[K, V])(implicit evidence$3: Ordering[V], evidence$4: Monoid[V]) extends MonoidAggregator[(K, V), SketchMap[K, V], SketchMap[K, V]] with Product with Serializable

    An Aggregator for the SketchMap.

    An Aggregator for the SketchMap. Can be created using SketchMap.aggregator

  303. case class SketchMapHash[K](hasher: CMSHash[Long], seed: Int)(implicit serialization: (K) => Array[Byte]) extends Product with Serializable

    Hashes an arbitrary key type to one that the Sketch Map can use.

  304. class SketchMapMonoid[K, V] extends Monoid[SketchMap[K, V]] with CommutativeMonoid[SketchMap[K, V]]

    Responsible for creating instances of SketchMap.

  305. case class SketchMapParams[K](seed: Int, width: Int, depth: Int, heavyHittersCount: Int)(implicit serialization: (K) => Array[Byte]) extends Product with Serializable

    Convenience class for holding constant parameters of a Sketch Map.

  306. sealed abstract class SpaceSaver[T] extends AnyRef

    Data structure used in the Space-Saving Algorithm to find the approximate most frequent and top-k elements.

    Data structure used in the Space-Saving Algorithm to find the approximate most frequent and top-k elements. The algorithm is described in "Efficient Computation of Frequent and Top-k Elements in Data Streams". See here: www.cs.ucsb.edu/research/tech_reports/reports/2005-23.pdf In the paper the data structure is called StreamSummary but we chose to call it SpaceSaver instead. Note that the adaptation to hadoop and parallelization were not described in the article and have not been proven to be mathematically correct or preserve the guarantees or benefits of the algorithm.

  307. class SpaceSaverSemigroup[T] extends Semigroup[SpaceSaver[T]]
  308. case class SparseCMS[K](exactCountTable: Map[K, Long], totalCount: Long, params: CMSParams[K]) extends CMS[K] with Product with Serializable

    A sparse Count-Min sketch structure, used for situations where the key is highly skewed.

  309. case class SparseHLL(bits: Int, maxRhow: Map[Int, Max[Byte]]) extends HLL with Product with Serializable
  310. case class SparseVector[V](map: Map[Int, V], sparseValue: V, length: Int) extends AdaptiveVector[V] with Product with Serializable
  311. trait StatefulSummer[V] extends Buffered[V, V]

    A Stateful summer is something that is potentially more efficient (a buffer, a cache, etc...) that has the same result as a sum: Law 1: Semigroup.sumOption(items) == (Monoid.plus(items.map { stateful.put(_) }.filter { _.isDefined }, stateful.flush) && stateful.isFlushed) Law 2: isFlushed == flush.isEmpty

  312. trait Successible[T] extends Serializable

    This is a typeclass to represent things which increase.

    This is a typeclass to represent things which increase. Note that it is important that a value after being incremented is always larger than it was before. Note that next returns Option because this class comes with the notion of the "greatest" key, which is None. Ints, for example, will cycle if next(java.lang.Integer.MAX_VALUE) is called, therefore we need a notion of what happens when we hit the bounds at which our ordering is violating. This is also useful for closed sets which have a fixed progression.

  313. class SumAll[V] extends StatefulSummer[V]

    Sum the entire iterator one item at a time.

    Sum the entire iterator one item at a time. Only emits on flush you should probably prefer BufferedSumAll

  314. class SummingCache[K, V] extends StatefulSummer[Map[K, V]]

    A Stateful Summer on Map[K,V] that keeps a cache of recent keys

  315. class SummingIterator[V] extends Serializable with Iterator[V]
  316. class SummingQueue[V] extends StatefulSummer[V]
  317. class SummingWithHitsCache[K, V] extends SummingCache[K, V]

    A SummingCache that also tracks the number of key hits

  318. sealed abstract class TopCMS[K] extends Serializable with CMSCounting[K, TopCMS] with CMSHeavyHitters[K]

    A Count-Min sketch data structure that allows for (a) counting and frequency estimation of elements in a data stream and (b) tracking the heavy hitters among these elements.

    A Count-Min sketch data structure that allows for (a) counting and frequency estimation of elements in a data stream and (b) tracking the heavy hitters among these elements.

    The logic of how heavy hitters are computed is pluggable, see HeavyHittersLogic.

    Tip: If you do not need to track heavy hitters, take a look at CMS, which is more efficient in this case.

    Usage

    This example demonstrates how to count Long elements with TopCMS, i.e. K=Long.

    Note that the actual counting is always performed with a Long, regardless of your choice of K. That is, the counting table behind the scenes is backed by Long values (at least in the current implementation), and thus the returned frequency estimates are always instances of Approximate[Long].

    K

    The type used to identify the elements to be counted.

    Example:
    1. // Creates a monoid for a CMS that can count `Long` elements.
      val topPctCMSMonoid: TopPctCMSMonoid[Long] = {
        val eps = 0.001
        val delta = 1E-10
        val seed = 1
        val heavyHittersPct = 0.1
        TopPctCMS.monoid[Long](eps, delta, seed, heavyHittersPct)
      }
      
      // Creates a TopCMS instance that has counted the element `1L`.
      val topCMS: TopCMS[Long] = topPctCMSMonoid.create(1L)
      
      // Estimates the frequency of `1L`
      val estimate: Approximate[Long] = topCMS.frequency(1L)
      
      // What are the heavy hitters so far?
      val heavyHitters: Set[Long] = topCMS.heavyHitters
  319. class TopCMSAggregator[K] extends MonoidAggregator[K, TopCMS[K], TopCMS[K]]
  320. case class TopCMSInstance[K](cms: CMS[K], hhs: HeavyHitters[K], params: TopCMSParams[K]) extends TopCMS[K] with Product with Serializable
  321. case class TopCMSItem[K](item: K, cms: CMS[K], params: TopCMSParams[K]) extends TopCMS[K] with Product with Serializable

    Used for holding a single element, to avoid repeatedly adding elements from sparse counts tables.

  322. class TopCMSMonoid[K] extends Monoid[TopCMS[K]]
  323. case class TopCMSParams[K](logic: HeavyHittersLogic[K]) extends Product with Serializable
  324. case class TopCMSZero[K](cms: CMS[K], params: TopCMSParams[K]) extends TopCMS[K] with Product with Serializable

    Zero element.

    Zero element. Used for initialization.

  325. case class TopK[N](size: Int, items: List[N], max: Option[N]) extends Product with Serializable
  326. class TopKMonoid[T] extends Monoid[TopK[T]]

    A top-k monoid that is much faster than SortedListTake equivalent to: (left ++ right).sorted.take(k) but doesn't do a total sort If you can handle the mutability, mutable.PriorityQueueMonoid is even faster.

    A top-k monoid that is much faster than SortedListTake equivalent to: (left ++ right).sorted.take(k) but doesn't do a total sort If you can handle the mutability, mutable.PriorityQueueMonoid is even faster.

    NOTE!!!! This assumes the inputs are already sorted! resorting each time kills speed

  327. class TopKToListAggregator[A] extends MonoidAggregator[A, TopK[A], List[A]]
  328. case class TopNCMSAggregator[K](cmsMonoid: TopNCMSMonoid[K]) extends TopCMSAggregator[K] with Product with Serializable

    An Aggregator for TopNCMS.

    An Aggregator for TopNCMS. Can be created using TopNCMS.aggregator.

  329. class TopNCMSMonoid[K] extends TopCMSMonoid[K]

    Monoid for top-N based TopCMS sketches.

    Monoid for top-N based TopCMS sketches. Use with care! (see warning below)

    Warning: Adding top-N CMS instances (++) is an unsafe operation

    Top-N computations are not associative. The effect is that a top-N CMS has an ordering bias (with regard to heavy hitters) when merging CMS instances (e.g. via ++). This means merging heavy hitters across CMS instances may lead to incorrect, biased results: the outcome is biased by the order in which CMS instances / heavy hitters are being merged, with the rule of thumb being that the earlier a set of heavy hitters is being merged, the more likely is the end result biased towards these heavy hitters.

    The warning above only applies when adding CMS instances (think: cms1 ++ cms2). In comparison, heavy hitters are correctly computed when:

    • a top-N CMS instance is created from a single data stream, i.e. Seq[K]
    • items are added/counted individually, i.e. cms + item or cms + (item, count).

    See the discussion in Algebird issue 353 for further details.

    Alternatives

    The following, alternative data structures may be better picks than a top-N based CMS given the warning above:

    • TopPctCMS: Has safe merge semantics for its instances including heavy hitters.
    • SpaceSaver: Has the same ordering bias than a top-N CMS, but at least it provides bounds on the bias.

    Usage

    The type K is the type of items you want to count. You must provide an implicit CMSHasher[K] for K, and Algebird ships with several such implicits for commonly used types such as Long and BigInt.

    If your type K is not supported out of the box, you have two options: 1) You provide a "translation" function to convert items of your (unsupported) type K to a supported type such as Double, and then use the contramap function of CMSHasher to create the required CMSHasher[K] for your type (see the documentation of CMSHasher for an example); 2) You implement a CMSHasher[K] from scratch, using the existing CMSHasher implementations as a starting point.

    Note: Because Arrays in Scala/Java not have sane equals and hashCode implementations, you cannot safely use types such as Array[Byte]. Extra work is required for Arrays. For example, you may opt to convert Array[T] to a Seq[T] via toSeq, or you can provide appropriate wrapper classes. Algebird provides one such wrapper class, Bytes, to safely wrap an Array[Byte] for use with CMS.

    K

    The type used to identify the elements to be counted. For example, if you want to count the occurrence of user names, you could map each username to a unique numeric ID expressed as a Long, and then count the occurrences of those Longs with a CMS of type K=Long. Note that this mapping between the elements of your problem domain and their identifiers used for counting via CMS should be bijective. We require a CMSHasher context bound for K, see CMSHasher for available implicits that can be imported. Which type K should you pick in practice? For domains that have less than 2^64 unique elements, you'd typically use Long. For larger domains you can try BigInt, for example.

  330. case class TopNLogic[K](heavyHittersN: Int) extends HeavyHittersLogic[K] with Product with Serializable

    Tracks the top N heavy hitters, where N is defined by heavyHittersN.

    Tracks the top N heavy hitters, where N is defined by heavyHittersN.

    Warning: top-N computations are not associative. The effect is that a top-N CMS has an ordering bias (with regard to heavy hitters) when merging instances. This means merging heavy hitters across CMS instances may lead to incorrect, biased results: the outcome is biased by the order in which CMS instances / heavy hitters are being merged, with the rule of thumb being that the earlier a set of heavy hitters is being merged, the more likely is the end result biased towards these heavy hitters.

    See also

    Discussion in Algebird issue 353

  331. case class TopPctCMSAggregator[K](cmsMonoid: TopPctCMSMonoid[K]) extends TopCMSAggregator[K] with Product with Serializable

    An Aggregator for TopPctCMS.

    An Aggregator for TopPctCMS. Can be created using TopPctCMS.aggregator.

  332. class TopPctCMSMonoid[K] extends TopCMSMonoid[K]

    Monoid for Top-% based TopCMS sketches.

    Monoid for Top-% based TopCMS sketches.

    Usage

    The type K is the type of items you want to count. You must provide an implicit CMSHasher[K] for K, and Algebird ships with several such implicits for commonly used types such as Long and BigInt.

    If your type K is not supported out of the box, you have two options: 1) You provide a "translation" function to convert items of your (unsupported) type K to a supported type such as Double, and then use the contramap function of CMSHasher to create the required CMSHasher[K] for your type (see the documentation of CMSHasher for an example); 2) You implement a CMSHasher[K] from scratch, using the existing CMSHasher implementations as a starting point.

    Note: Because Arrays in Scala/Java not have sane equals and hashCode implementations, you cannot safely use types such as Array[Byte]. Extra work is required for Arrays. For example, you may opt to convert Array[T] to a Seq[T] via toSeq, or you can provide appropriate wrapper classes. Algebird provides one such wrapper class, Bytes, to safely wrap an Array[Byte] for use with CMS.

    K

    The type used to identify the elements to be counted. For example, if you want to count the occurrence of user names, you could map each username to a unique numeric ID expressed as a Long, and then count the occurrences of those Longs with a CMS of type K=Long. Note that this mapping between the elements of your problem domain and their identifiers used for counting via CMS should be bijective. We require a CMSHasher context bound for K, see CMSHasher for available implicits that can be imported. Which type K should you pick in practice? For domains that have less than 2^64 unique elements, you'd typically use Long. For larger domains you can try BigInt, for example.

  333. case class TopPctLogic[K](heavyHittersPct: Double) extends HeavyHittersLogic[K] with Product with Serializable

    Finds all heavy hitters, i.e., elements in the stream that appear at least (heavyHittersPct * totalCount) times.

    Finds all heavy hitters, i.e., elements in the stream that appear at least (heavyHittersPct * totalCount) times.

    Every item that appears at least (heavyHittersPct * totalCount) times is output, and with probability p >= 1 - delta, no item whose count is less than (heavyHittersPct - eps) * totalCount is output.

    This also means that this parameter is an upper bound on the number of heavy hitters that will be tracked: the set of heavy hitters contains at most 1 / heavyHittersPct elements. For example, if heavyHittersPct=0.01 (or 0.25), then at most 1 / 0.01 = 100 items (or 1 / 0.25 = 4 items) will be tracked/returned as heavy hitters. This parameter can thus control the memory footprint required for tracking heavy hitters.

  334. class Tuple10Group[A, B, C, D, E, F, G, H, I, J] extends Tuple10Monoid[A, B, C, D, E, F, G, H, I, J] with Group[(A, B, C, D, E, F, G, H, I, J)]

    Combine 10 groups into a product group

  335. class Tuple10Monoid[A, B, C, D, E, F, G, H, I, J] extends Tuple10Semigroup[A, B, C, D, E, F, G, H, I, J] with Monoid[(A, B, C, D, E, F, G, H, I, J)]

    Combine 10 monoids into a product monoid

  336. class Tuple10Ring[A, B, C, D, E, F, G, H, I, J] extends Tuple10Group[A, B, C, D, E, F, G, H, I, J] with Ring[(A, B, C, D, E, F, G, H, I, J)]

    Combine 10 rings into a product ring

  337. class Tuple10Semigroup[A, B, C, D, E, F, G, H, I, J] extends Semigroup[(A, B, C, D, E, F, G, H, I, J)]

    Combine 10 semigroups into a product semigroup

  338. class Tuple11Group[A, B, C, D, E, F, G, H, I, J, K] extends Tuple11Monoid[A, B, C, D, E, F, G, H, I, J, K] with Group[(A, B, C, D, E, F, G, H, I, J, K)]

    Combine 11 groups into a product group

  339. class Tuple11Monoid[A, B, C, D, E, F, G, H, I, J, K] extends Tuple11Semigroup[A, B, C, D, E, F, G, H, I, J, K] with Monoid[(A, B, C, D, E, F, G, H, I, J, K)]

    Combine 11 monoids into a product monoid

  340. class Tuple11Ring[A, B, C, D, E, F, G, H, I, J, K] extends Tuple11Group[A, B, C, D, E, F, G, H, I, J, K] with Ring[(A, B, C, D, E, F, G, H, I, J, K)]

    Combine 11 rings into a product ring

  341. class Tuple11Semigroup[A, B, C, D, E, F, G, H, I, J, K] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K)]

    Combine 11 semigroups into a product semigroup

  342. class Tuple12Group[A, B, C, D, E, F, G, H, I, J, K, L] extends Tuple12Monoid[A, B, C, D, E, F, G, H, I, J, K, L] with Group[(A, B, C, D, E, F, G, H, I, J, K, L)]

    Combine 12 groups into a product group

  343. class Tuple12Monoid[A, B, C, D, E, F, G, H, I, J, K, L] extends Tuple12Semigroup[A, B, C, D, E, F, G, H, I, J, K, L] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L)]

    Combine 12 monoids into a product monoid

  344. class Tuple12Ring[A, B, C, D, E, F, G, H, I, J, K, L] extends Tuple12Group[A, B, C, D, E, F, G, H, I, J, K, L] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L)]

    Combine 12 rings into a product ring

  345. class Tuple12Semigroup[A, B, C, D, E, F, G, H, I, J, K, L] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L)]

    Combine 12 semigroups into a product semigroup

  346. class Tuple13Group[A, B, C, D, E, F, G, H, I, J, K, L, M] extends Tuple13Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M)]

    Combine 13 groups into a product group

  347. class Tuple13Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M] extends Tuple13Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M)]

    Combine 13 monoids into a product monoid

  348. class Tuple13Ring[A, B, C, D, E, F, G, H, I, J, K, L, M] extends Tuple13Group[A, B, C, D, E, F, G, H, I, J, K, L, M] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M)]

    Combine 13 rings into a product ring

  349. class Tuple13Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M)]

    Combine 13 semigroups into a product semigroup

  350. class Tuple14Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Tuple14Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N)]

    Combine 14 groups into a product group

  351. class Tuple14Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Tuple14Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N)]

    Combine 14 monoids into a product monoid

  352. class Tuple14Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Tuple14Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N)]

    Combine 14 rings into a product ring

  353. class Tuple14Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N)]

    Combine 14 semigroups into a product semigroup

  354. class Tuple15Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Tuple15Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O)]

    Combine 15 groups into a product group

  355. class Tuple15Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Tuple15Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O)]

    Combine 15 monoids into a product monoid

  356. class Tuple15Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Tuple15Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O)]

    Combine 15 rings into a product ring

  357. class Tuple15Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O)]

    Combine 15 semigroups into a product semigroup

  358. class Tuple16Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Tuple16Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P)]

    Combine 16 groups into a product group

  359. class Tuple16Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Tuple16Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P)]

    Combine 16 monoids into a product monoid

  360. class Tuple16Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Tuple16Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P)]

    Combine 16 rings into a product ring

  361. class Tuple16Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P)]

    Combine 16 semigroups into a product semigroup

  362. class Tuple17Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Tuple17Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q)]

    Combine 17 groups into a product group

  363. class Tuple17Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Tuple17Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q)]

    Combine 17 monoids into a product monoid

  364. class Tuple17Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Tuple17Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q)]

    Combine 17 rings into a product ring

  365. class Tuple17Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q)]

    Combine 17 semigroups into a product semigroup

  366. class Tuple18Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Tuple18Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R)]

    Combine 18 groups into a product group

  367. class Tuple18Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Tuple18Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R)]

    Combine 18 monoids into a product monoid

  368. class Tuple18Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Tuple18Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R)]

    Combine 18 rings into a product ring

  369. class Tuple18Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R)]

    Combine 18 semigroups into a product semigroup

  370. class Tuple19Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Tuple19Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S)]

    Combine 19 groups into a product group

  371. class Tuple19Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Tuple19Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S)]

    Combine 19 monoids into a product monoid

  372. class Tuple19Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Tuple19Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S)]

    Combine 19 rings into a product ring

  373. class Tuple19Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S)]

    Combine 19 semigroups into a product semigroup

  374. class Tuple20Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Tuple20Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T)]

    Combine 20 groups into a product group

  375. class Tuple20Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Tuple20Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T)]

    Combine 20 monoids into a product monoid

  376. class Tuple20Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Tuple20Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T)]

    Combine 20 rings into a product ring

  377. class Tuple20Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T)]

    Combine 20 semigroups into a product semigroup

  378. class Tuple21Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Tuple21Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U)]

    Combine 21 groups into a product group

  379. class Tuple21Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Tuple21Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U)]

    Combine 21 monoids into a product monoid

  380. class Tuple21Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Tuple21Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U)]

    Combine 21 rings into a product ring

  381. class Tuple21Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U)]

    Combine 21 semigroups into a product semigroup

  382. class Tuple22Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Tuple22Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] with Group[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V)]

    Combine 22 groups into a product group

  383. class Tuple22Monoid[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Tuple22Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] with Monoid[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V)]

    Combine 22 monoids into a product monoid

  384. class Tuple22Ring[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Tuple22Group[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] with Ring[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V)]

    Combine 22 rings into a product ring

  385. class Tuple22Semigroup[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Semigroup[(A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V)]

    Combine 22 semigroups into a product semigroup

  386. class Tuple2Group[A, B] extends Tuple2Monoid[A, B] with Group[(A, B)]

    Combine 2 groups into a product group

  387. class Tuple2Monoid[A, B] extends Tuple2Semigroup[A, B] with Monoid[(A, B)]

    Combine 2 monoids into a product monoid

  388. class Tuple2Ring[A, B] extends Tuple2Group[A, B] with Ring[(A, B)]

    Combine 2 rings into a product ring

  389. class Tuple2Semigroup[A, B] extends Semigroup[(A, B)]

    Combine 2 semigroups into a product semigroup

  390. class Tuple3Group[A, B, C] extends Tuple3Monoid[A, B, C] with Group[(A, B, C)]

    Combine 3 groups into a product group

  391. class Tuple3Monoid[A, B, C] extends Tuple3Semigroup[A, B, C] with Monoid[(A, B, C)]

    Combine 3 monoids into a product monoid

  392. class Tuple3Ring[A, B, C] extends Tuple3Group[A, B, C] with Ring[(A, B, C)]

    Combine 3 rings into a product ring

  393. class Tuple3Semigroup[A, B, C] extends Semigroup[(A, B, C)]

    Combine 3 semigroups into a product semigroup

  394. class Tuple4Group[A, B, C, D] extends Tuple4Monoid[A, B, C, D] with Group[(A, B, C, D)]

    Combine 4 groups into a product group

  395. class Tuple4Monoid[A, B, C, D] extends Tuple4Semigroup[A, B, C, D] with Monoid[(A, B, C, D)]

    Combine 4 monoids into a product monoid

  396. class Tuple4Ring[A, B, C, D] extends Tuple4Group[A, B, C, D] with Ring[(A, B, C, D)]

    Combine 4 rings into a product ring

  397. class Tuple4Semigroup[A, B, C, D] extends Semigroup[(A, B, C, D)]

    Combine 4 semigroups into a product semigroup

  398. class Tuple5Group[A, B, C, D, E] extends Tuple5Monoid[A, B, C, D, E] with Group[(A, B, C, D, E)]

    Combine 5 groups into a product group

  399. class Tuple5Monoid[A, B, C, D, E] extends Tuple5Semigroup[A, B, C, D, E] with Monoid[(A, B, C, D, E)]

    Combine 5 monoids into a product monoid

  400. class Tuple5Ring[A, B, C, D, E] extends Tuple5Group[A, B, C, D, E] with Ring[(A, B, C, D, E)]

    Combine 5 rings into a product ring

  401. class Tuple5Semigroup[A, B, C, D, E] extends Semigroup[(A, B, C, D, E)]

    Combine 5 semigroups into a product semigroup

  402. class Tuple6Group[A, B, C, D, E, F] extends Tuple6Monoid[A, B, C, D, E, F] with Group[(A, B, C, D, E, F)]

    Combine 6 groups into a product group

  403. class Tuple6Monoid[A, B, C, D, E, F] extends Tuple6Semigroup[A, B, C, D, E, F] with Monoid[(A, B, C, D, E, F)]

    Combine 6 monoids into a product monoid

  404. class Tuple6Ring[A, B, C, D, E, F] extends Tuple6Group[A, B, C, D, E, F] with Ring[(A, B, C, D, E, F)]

    Combine 6 rings into a product ring

  405. class Tuple6Semigroup[A, B, C, D, E, F] extends Semigroup[(A, B, C, D, E, F)]

    Combine 6 semigroups into a product semigroup

  406. class Tuple7Group[A, B, C, D, E, F, G] extends Tuple7Monoid[A, B, C, D, E, F, G] with Group[(A, B, C, D, E, F, G)]

    Combine 7 groups into a product group

  407. class Tuple7Monoid[A, B, C, D, E, F, G] extends Tuple7Semigroup[A, B, C, D, E, F, G] with Monoid[(A, B, C, D, E, F, G)]

    Combine 7 monoids into a product monoid

  408. class Tuple7Ring[A, B, C, D, E, F, G] extends Tuple7Group[A, B, C, D, E, F, G] with Ring[(A, B, C, D, E, F, G)]

    Combine 7 rings into a product ring

  409. class Tuple7Semigroup[A, B, C, D, E, F, G] extends Semigroup[(A, B, C, D, E, F, G)]

    Combine 7 semigroups into a product semigroup

  410. class Tuple8Group[A, B, C, D, E, F, G, H] extends Tuple8Monoid[A, B, C, D, E, F, G, H] with Group[(A, B, C, D, E, F, G, H)]

    Combine 8 groups into a product group

  411. class Tuple8Monoid[A, B, C, D, E, F, G, H] extends Tuple8Semigroup[A, B, C, D, E, F, G, H] with Monoid[(A, B, C, D, E, F, G, H)]

    Combine 8 monoids into a product monoid

  412. class Tuple8Ring[A, B, C, D, E, F, G, H] extends Tuple8Group[A, B, C, D, E, F, G, H] with Ring[(A, B, C, D, E, F, G, H)]

    Combine 8 rings into a product ring

  413. class Tuple8Semigroup[A, B, C, D, E, F, G, H] extends Semigroup[(A, B, C, D, E, F, G, H)]

    Combine 8 semigroups into a product semigroup

  414. class Tuple9Group[A, B, C, D, E, F, G, H, I] extends Tuple9Monoid[A, B, C, D, E, F, G, H, I] with Group[(A, B, C, D, E, F, G, H, I)]

    Combine 9 groups into a product group

  415. class Tuple9Monoid[A, B, C, D, E, F, G, H, I] extends Tuple9Semigroup[A, B, C, D, E, F, G, H, I] with Monoid[(A, B, C, D, E, F, G, H, I)]

    Combine 9 monoids into a product monoid

  416. class Tuple9Ring[A, B, C, D, E, F, G, H, I] extends Tuple9Group[A, B, C, D, E, F, G, H, I] with Ring[(A, B, C, D, E, F, G, H, I)]

    Combine 9 rings into a product ring

  417. class Tuple9Semigroup[A, B, C, D, E, F, G, H, I] extends Semigroup[(A, B, C, D, E, F, G, H, I)]

    Combine 9 semigroups into a product semigroup

  418. case class Universe[T]() extends Interval[T] with Product with Serializable
  419. class UnsafeFromAlgebraRig[T] extends Ring[T]

    In some legacy cases, we have implemented Rings where we lacked the full laws.

    In some legacy cases, we have implemented Rings where we lacked the full laws. This allows you to be precise (only implement the structure you have), but unsafely use it as a Ring in legacy code that is expecting a Ring.

  420. class UnsafeFromAlgebraRng[T] extends Ring[T]

    In some legacy cases, we have implemented Rings where we lacked the full laws.

    In some legacy cases, we have implemented Rings where we lacked the full laws. This allows you to be precise (only implement the structure you have), but unsafely use it as a Ring in legacy code that is expecting a Ring.

  421. sealed trait Upper[T] extends Interval[T]
  422. trait VectorSpace[F, C[_]] extends Serializable
    Annotations
    @implicitNotFound()
  423. sealed trait VectorSpaceOps extends AnyRef
  424. case class Window[T](total: T, items: Queue[T]) extends Product with Serializable

    Convenience case class defined with a monoid for aggregating elements over a finite window.

    Convenience case class defined with a monoid for aggregating elements over a finite window.

    total

    Known running total of T

    items

    queue of known trailing elements. Example usage: case class W28[T](window: Window[T]) { def total = this.window.total def items = this.window.items def size = this.window.size } object W28 { val windowSize = 28 def apply[T](v: T): W28[T] = W28[T](Window(v)) implicit def w28Monoid[T](implicit p: Priority[Group[T], Monoid[T]]): Monoid[W28[T]] = new Monoid[W28[T]] { private val WT: Monoid[Window[T]] = Window.monoid[T](windowSize) def zero = W28[T](WT.zero) def plus(a: W28[T], b: W28[T]): W28[T] = W28[T](WT.plus(a.window, b.window)) } } val elements = getElements() val trailing90Totals = elements .map{ W90 } .scanLeft(W90(0)) { (a, b) => a + b } .map{ _.total }

  425. abstract class WindowMonoid[T] extends Monoid[Window[T]]

    Provides a natural monoid for combining windows truncated to some window size.

  426. final case class WindowMonoidFromGroup[T](windowSize: Int)(implicit group: Group[T]) extends WindowMonoid[T] with Product with Serializable
  427. final case class WindowMonoidFromMonoid[T](windowSize: Int)(implicit m: Monoid[T]) extends WindowMonoid[T] with Product with Serializable

Deprecated Type Members

  1. case class BitSetLite(in: Array[Byte]) extends Product with Serializable

    A super lightweight (hopefully) version of BitSet

    A super lightweight (hopefully) version of BitSet

    Annotations
    @deprecated
    Deprecated

    (Since version 0.12.3) This is no longer used.

  2. class MinusOp[T] extends AnyRef
    Annotations
    @deprecated
    Deprecated

    (Since version 0.13.8) use Operators.Ops

  3. class PlusOp[T] extends AnyRef
    Annotations
    @deprecated
    Deprecated

    (Since version 0.13.8) use Operators.Ops

  4. class TimesOp[T] extends AnyRef
    Annotations
    @deprecated
    Deprecated

    (Since version 0.13.8) use Operators.Ops

Value Members

  1. val Field: algebra.ring.Field.type
  2. object AdaptiveVector

    Some functions to create or convert AdaptiveVectors

  3. object AdjoinedUnit extends Serializable
  4. object AffineFunction extends Serializable
  5. object Aggregator extends Serializable

    Aggregators compose well.

    Aggregators compose well.

    To create a parallel aggregator that operates on a single input in parallel, use: GeneratedTupleAggregator.from2((agg1, agg2))

  6. object AndVal extends Serializable
  7. object AndValMonoid extends Monoid[AndVal]

    Boolean AND monoid.

    Boolean AND monoid. plus means logical AND, zero is true.

  8. object Applicative

    Follows the type-class pattern for the Applicative trait

  9. object Approximate extends Serializable
  10. object ApproximateBoolean extends Serializable
  11. object ArrayBufferedOperation extends Serializable
  12. object AveragedGroup extends Group[AveragedValue] with CommutativeGroup[AveragedValue]

    Group implementation for AveragedValue.

  13. object AveragedValue extends Serializable

    Provides a set of operations needed to create and use AveragedValue instances.

  14. object Averager extends MonoidAggregator[Double, AveragedValue, Double]

    Aggregator that uses AveragedValue to calculate the mean of all Double values in the stream.

    Aggregator that uses AveragedValue to calculate the mean of all Double values in the stream. Each Double value receives a count of 1 during aggregation.

  15. object BF extends Serializable
  16. object BFInstance extends Serializable
  17. object Batched extends Serializable
  18. object BigDecimalRing extends NumericRing[BigDecimal]
  19. object BigIntRing extends NumericRing[BigInt]
  20. object BloomFilter
  21. object BloomFilterAggregator extends Serializable
  22. object BooleanRing extends Ring[Boolean]
  23. object Bytes extends Serializable
  24. object CMS extends Serializable
  25. object CMSFunctions

    Helper functions to generate or to translate between various CMS parameters (cf.

    Helper functions to generate or to translate between various CMS parameters (cf. CMSParams).

  26. object CMSHasher extends Serializable
  27. object CMSHasherImplicits

    This formerly held the instances that moved to object CMSHasher

    This formerly held the instances that moved to object CMSHasher

    These instances are slow, but here for compatibility with old serialized data. For new code, avoid these and instead use the implicits found in the CMSHasher companion object.

  28. object CMSInstance extends Serializable
  29. object Correlation extends Serializable
  30. object CorrelationAggregator extends MonoidAggregator[(Double, Double), Correlation, Correlation]
  31. object CorrelationMonoid extends Monoid[Correlation]
  32. object DecayedValue extends Serializable
  33. object DecayedVector extends CompatDecayedVector with Serializable

    Represents a container class together with time.

    Represents a container class together with time. Its monoid consists of exponentially scaling the older value and summing with the newer one.

  34. object DecayingCMS extends Serializable
  35. object DoubleRing extends Ring[Double]
  36. object ExpHist extends Serializable
  37. object First extends FirstInstances with Serializable

    Provides a set of operations and typeclass instances needed to use First instances.

  38. object FlatMapPreparer extends Serializable
  39. object FloatRing extends Ring[Float]
  40. object Fold extends CompatFold with Serializable

    Methods to create and run Folds.

    Methods to create and run Folds.

    The Folds defined here are immutable and serializable, which we expect by default. It is important that you as a user indicate mutability or non-serializability when defining new Folds. Additionally, it is recommended that "end" functions not mutate the accumulator in order to support scans (producing a stream of intermediate outputs by calling "end" at each step).

  41. object Functor

    Follows the type-class pattern for the Functor trait

  42. object GeneratedTupleAggregator extends GeneratedTupleAggregator
  43. object Group extends GeneratedGroupImplicits with ProductGroups with FromAlgebraGroupImplicit0 with Serializable
  44. object Hash128 extends Serializable

    This gives default hashes using Murmur128 with a seed of 12345678 (for no good reason, but it should not be changed lest we break serialized HLLs)

  45. object HeavyHitters extends Serializable
  46. object HyperLogLog

    Implementation of the HyperLogLog approximate counting as a Monoid

    Implementation of the HyperLogLog approximate counting as a Monoid

    See also

    http://algo.inria.fr/flajolet/Publications/FlFuGaMe07.pdf HyperLogLog: the analysis of a near-optimal cardinality estimation algorithm Philippe Flajolet and Éric Fusy and Olivier Gandouet and Frédéric Meunier

  47. object HyperLogLogAggregator extends Serializable

    This object makes it easier to create Aggregator instances that use HLL

  48. object Identity extends Serializable
  49. object IdentityMonad extends Monad[Identity]
  50. object IntRing extends Ring[Int]
  51. object IntegralPredecessible extends Serializable
  52. object IntegralSuccessible extends Serializable
  53. object Interval extends Serializable
  54. object JBoolRing extends Ring[Boolean]
  55. object JDoubleRing extends Ring[Double]
  56. object JFloatRing extends Ring[Float]
  57. object JIntRing extends Ring[Integer]
  58. object JLongRing extends Ring[Long]
  59. object JShortRing extends Ring[Short]
  60. object Last extends LastInstances with Serializable

    Provides a set of operations and typeclass instances needed to use Last instances.

  61. object LongRing extends Ring[Long]
  62. object MapAggregator extends Serializable
  63. object MapAlgebra
  64. object MapPreparer extends Serializable
  65. object Max extends MaxInstances with Serializable

    Provides a set of operations and typeclass instances needed to use Max instances.

  66. object Metric extends Serializable

    A Metric[V] m is a function (V, V) => Double that satisfies the following properties:

    A Metric[V] m is a function (V, V) => Double that satisfies the following properties:

    1. m(v1, v2) >= 0 2. m(v1, v2) == 0 iff v1 == v2 3. m(v1, v2) == m(v2, v1) 4. m(v1, v3) <= m(v1, v2) + m(v2, v3)

    If you implement this trait, make sure that you follow these rules.

  67. object Min extends MinInstances with Serializable

    Provides a set of operations and typeclass instances needed to use Min instances.

  68. object MinHasher extends Serializable
  69. object MinPlus extends Serializable
  70. case object MinPlusZero extends MinPlus[Nothing] with Product with Serializable
  71. object Moments extends Serializable
  72. object MomentsAggregator extends MonoidAggregator[Double, Moments, Moments]
  73. object Monad

    Follows the type-class pattern for the Monad trait

  74. object Monoid extends GeneratedMonoidImplicits with ProductMonoids with FromAlgebraMonoidImplicit0 with Serializable
  75. object MultiAggregator
  76. object NullGroup extends ConstantGroup[Null]
  77. object Operators
  78. object OrVal extends Serializable
  79. object OrValMonoid extends Monoid[OrVal]

    Boolean OR monoid.

    Boolean OR monoid. plus means logical OR, zero is false.

  80. object Predecessible extends Serializable
  81. object Preparer extends Serializable
  82. object Priority extends FindPreferred
  83. object QTree extends Serializable

    A QTree provides an approximate Map[Double,A:Monoid] suitable for range queries, quantile queries, and combinations of these (for example, if you use a numeric A, you can derive the inter-quartile mean).

    A QTree provides an approximate Map[Double,A:Monoid] suitable for range queries, quantile queries, and combinations of these (for example, if you use a numeric A, you can derive the inter-quartile mean).

    It is loosely related to the Q-Digest data structure from http://www.cs.virginia.edu/~son/cs851/papers/ucsb.sensys04.pdf, but using an immutable tree structure, and carrying a generalized sum (of type A) at each node instead of just a count.

    The basic idea is to keep a binary tree, where the root represents the entire range of the input keys, and each child node represents either the lower or upper half of its parent's range. Ranges are constrained to be dyadic intervals (https://en.wikipedia.org/wiki/Interval_(mathematics)#Dyadic_intervals) for ease of merging.

    To keep the size bounded, the total count carried by any sub-tree must be at least 1/(2^k) of the total count at the root. Any sub-trees that do not meet this criteria have their children pruned and become leaves. (It's important that they not be pruned away entirely, but that we keep a fringe of low-count leaves that can gain weight over time and ultimately split again when warranted).

    Quantile and range queries both give hard upper and lower bounds; the true result will be somewhere in the range given.

    Keys must be >= 0.

  84. object QTreeAggregator extends Serializable
  85. object ResetState
  86. object RichCBitSet
  87. object RightFolded

    This is an associative, but not commutative monoid Also, you must start on the right, with a value, and all subsequent RightFolded must be RightFoldedToFold objects or zero

    This is an associative, but not commutative monoid Also, you must start on the right, with a value, and all subsequent RightFolded must be RightFoldedToFold objects or zero

    If you add two Folded values together, you always get the one on the left, so this forms a kind of reset of the fold.

  88. object RightFolded2

    This monoid takes a list of values of type In or Out, and folds to the right all the Ins into Out values, leaving you with a list of Out values, then finally, maps those outs onto Acc, where there is a group, and adds all the Accs up.

    This monoid takes a list of values of type In or Out, and folds to the right all the Ins into Out values, leaving you with a list of Out values, then finally, maps those outs onto Acc, where there is a group, and adds all the Accs up. So, if you have a list: I I I O I O O I O I O the monoid is equivalent to the computation:

    map(fold(List(I,I,I),O)) + map(fold(List(I),O)) + map(fold(List(),O)) + map(fold(List(I),O)) + map(fold(List(I),O))

    This models a version of the map/reduce paradigm, where the fold happens on the mappers for each group on Ins, and then they are mapped to Accs, sent to a single reducer and all the Accs are added up.

  89. case object RightFoldedZero extends RightFolded[Nothing, Nothing] with Product with Serializable
  90. case object RightFoldedZero2 extends RightFolded2[Nothing, Nothing, Nothing] with Product with Serializable
  91. object Ring extends GeneratedRingImplicits with ProductRings with RingImplicits0 with Serializable
  92. object SGD
  93. object SGDPos extends Serializable
  94. object SGDWeights extends Serializable
  95. case object SGDZero extends SGD[Nothing] with Product with Serializable
  96. object SSMany extends Serializable
  97. object Scan extends Serializable
  98. object ScopedTopNCMS
  99. object Semigroup extends GeneratedSemigroupImplicits with ProductSemigroups with FromAlgebraSemigroupImplicit0 with Serializable
  100. object SetDiff extends Serializable
  101. object ShortRing extends Ring[Short]
  102. object SketchMap extends Serializable

    Data structure representing an approximation of Map[K, V], where V has an implicit ordering and monoid.

    Data structure representing an approximation of Map[K, V], where V has an implicit ordering and monoid. This is a more generic version of CountMinSketch.

    Values are stored in valuesTable, a 2D vector containing aggregated sums of values inserted to the Sketch Map.

    The data structure stores top non-zero values, called Heavy Hitters. The values are sorted by an implicit reverse ordering for the value, and the number of heavy hitters stored is based on the heavyHittersCount set in params.

    Use SketchMapMonoid to create instances of this class.

  103. object SketchMapParams extends Serializable
  104. object SpaceSaver
  105. object SparseCMS extends Serializable
  106. object StringMonoid extends Monoid[String]
  107. object Successible extends Serializable
  108. object SummingCache extends Serializable
  109. object SummingIterator extends Serializable

    Creates an Iterator that emits partial sums of an input Iterator[V].

    Creates an Iterator that emits partial sums of an input Iterator[V]. Generally this is useful to change from processing individual Vs to possibly blocks of V @see SummingQueue or a cache of recent Keys in a V=Map[K,W] case: @see SummingCache

  110. object SummingQueue extends Serializable
  111. object SummingWithHitsCache extends Serializable
  112. object TopCMSInstance extends Serializable
  113. object TopKMonoid extends Serializable
  114. object TopNCMS
  115. object TopPctCMS
  116. object UnitGroup extends ConstantGroup[Unit]
  117. object VectorSpace extends VectorSpaceOps with Implicits with Serializable

    This class represents a vector space.

    This class represents a vector space. For the required properties see:

    http://en.wikipedia.org/wiki/Vector_space#Definition

  118. object Window extends Serializable
  119. object field

    This is here to ease transition to using algebra.Field as the field type.

    This is here to ease transition to using algebra.Field as the field type. Intended use is to do:

    {code} import com.twitter.algebird.field._ {/code}

    Note, this are not strictly lawful since floating point arithmetic using IEEE-754 is only approximately associative and distributive.

Deprecated Value Members

  1. object MomentsGroup extends MomentsMonoid with Group[Moments] with CommutativeGroup[Moments]

    This should not be used as a group (avoid negate and minus).

    This should not be used as a group (avoid negate and minus). It was wrongly believed that this was a group for several years in this code, however it was only being tested with positive counts (which is to say the generators were too weak). It isn't the case that minus and negate are totally wrong but (a - a) + b in general isn't associative: it won't equal a - (a - b) which it should.

    Annotations
    @deprecated
    Deprecated

    (Since version 0.13.8) use Moments.momentsMonoid, this isn't lawful for negative counts

Inherited from AnyRef

Inherited from Any

Ungrouped