StringColumn (tablesaw-core 0.35.0 API)

java.lang.Object
- tech.tablesaw.columns.AbstractColumn<String>
- - tech.tablesaw.columns.strings.AbstractStringColumn
  - - tech.tablesaw.api.StringColumn

All Implemented Interfaces:

Iterable<String>, Comparator<String>, CategoricalColumn<String>, Column<String>, StringFilters, StringMapFunctions, StringReduceUtils, FilterSpec<Selection>, StringFilterSpec<Selection>
```
public class StringColumn
extends AbstractStringColumn
```
A column that contains String values. They are assumed to be 'categorical' rather than free-form text, so are stored in an encoding that takes advantage of the expected repetition of string values.
Because the MISSING_VALUE for this column type is an empty string, there is little or no need for special handling of missing values in this class's methods.

Field Summary
- Fields inherited from class tech.tablesaw.columns.AbstractColumn
  DEFAULT_ARRAY_SIZE

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`StringColumn`	`addAll(List<String> stringValues)` Add all the strings in the list to this column
`StringColumn`	`append(Column<String> column)`
`StringColumn`	`append(String value)` Added for naming consistency with all other columns
`StringColumn`	`appendCell(String object)`
`StringColumn`	`appendCell(String object, AbstractColumnParser<?> parser)`
`StringColumn`	`appendMissing()` Appends a missing value appropriate to the column
`StringColumn`	`appendObj(Object obj)`
`byte[]`	`asBytes(int rowNumber)` Returns the contents of the cell at rowNumber as a byte[]
`double[]`	`asDoubleArray()`
`DoubleColumn`	`asDoubleColumn()`
`List<String>`	`asList()` Returns a List<String> representation of all the values in this column
`String[]`	`asObjectArray()`
`Set<String>`	`asSet()`
`StringColumn`	`asStringColumn()` Returns a StringColumn consisting of the (unformatted) String representation of this column values
`TextColumn`	`asTextColumn()`
`void`	`clear()`
`boolean`	`contains(String aString)` Returns true if this column contains a cell with the given string, and false otherwise
`StringColumn`	`copy()` Returns a deep copy of the receiver
`Table`	`countByCategory()`
`int`	`countMissing()` Returns the count of missing values in this column
`int`	`countOccurrences(String value)`
`int`	`countUnique()` Returns the count of unique values in this column.
`static StringColumn`	`create(String name)`
`static StringColumn`	`create(String name, int size)`
`static StringColumn`	`create(String name, List<String> strings)`
`static StringColumn`	`create(String name, Stream<String> stream)`
`static StringColumn`	`create(String name, String[] strings)`
`static StringColumn`	`createInternal(String name, DictionaryMap map)`
`StringColumn`	`emptyCopy()` Returns a copy of the receiver with no data.
`StringColumn`	`emptyCopy(int rowSize)` Returns an empty copy of the receiver, with its internal storage initialized to the given row size.
`StringColumn`	`filter(Predicate<? super String> test)` Returns a new Column of the same type with only those rows satisfying the predicate
`StringColumn`	`first(int numRows)`
`int`	`firstIndexOf(String value)`
`String`	`get(int rowIndex)` Returns the value at rowIndex in this column.
`double`	`getDouble(int i)`
`List<BooleanColumn>`	`getDummies()` Returns a list of boolean columns suitable for use as dummy variables in, for example, regression analysis, select a column of categorical data must be encoded as a list of columns, such that each column represents a single category and indicates whether it is present (1) or not present (0)
`LookupTableWrapper`	`getLookupTable()` For tablesaw internal use only
`StringColumn`	`inRange(int start, int end)` Returns a column containing the rows in this column beginning with start inclusive, and ending with end exclusive
`boolean`	`isEmpty()` Returns true if the column has no data
`Selection`	`isEqualTo(String string)`
`Selection`	`isIn(Collection<String> strings)`
`Selection`	`isIn(String... strings)`
`boolean`	`isMissing(int rowNumber)`
`Selection`	`isNotEqualTo(String string)`
`Selection`	`isNotIn(Collection<String> strings)`
`Selection`	`isNotIn(String... strings)`
`Iterator<String>`	`iterator()`
`StringColumn`	`lag(int n)` Returns a column of the same type and size as the receiver, containing the receivers values offset by n.
`StringColumn`	`last(int numRows)`
`StringColumn`	`lead(int n)` Returns a column of the same type as the receiver, containing the receivers values offset -n For example if you lead a column containing 2, 3, 4 by 1, you get a column containing 3, 4, NA.
`StringColumn`	`map(Function<? super String,? extends String> fun)` Maps the function across all rows, appending the results to a new Column of the same type
`StringColumn`	`max(Column<String> other)` Returns a column containing the element-wise min between this column and other column
`StringColumn`	`min(Column<String> other)` Returns a column containing the element-wise min between this column and other column
`StringColumn`	`removeMissing()`
`it.unimi.dsi.fastutil.ints.IntComparator`	`rowComparator()`
`StringColumn`	`sampleN(int n)` Returns a column containing a random sample of the values in this column
`StringColumn`	`sampleX(double proportion)` Returns a table consisting of randomly selected values from this column.
`StringColumn`	`set(int rowIndex, String stringValue)`
`StringColumn`	`set(Selection condition, Column<String> other)` Updates this column where values matching the selection are replaced with the corresponding value from the given column
`StringColumn`	`set(Selection rowSelection, String newValue)` Conditionally update this column, replacing current values with newValue for all rows where the current value matches the selection criteria
`Column<String>`	`setMissing(int i)`
`StringColumn`	`setName(String name)` Sets the columns name to the given string
`int`	`size()` Returns the number of elements (a.k.a.
`void`	`sortAscending()`
`void`	`sortDescending()`
`StringColumn`	`sorted(Comparator<? super String> comp)` Returns a new Column of the same type sorted according to the provided Comparator
`StringColumn`	`subset(int[] rows)`
`Table`	`summary()`
`StringColumn`	`unique()` Returns a new Column containing all the unique values in this column
`static boolean`	`valueIsMissing(String string)`
`StringColumn`	`where(Selection selection)`

Methods inherited from class tech.tablesaw.columns.strings.AbstractStringColumn
append, bottom, byteSize, compare, getPrintFormatter, getString, getUnformattedString, set, setPrintFormatter, top

Methods inherited from class tech.tablesaw.columns.AbstractColumn
name, toString, type

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface tech.tablesaw.columns.strings.StringFilters
containsString, endsWith, equalsIgnoreCase, equalsIgnoreCase, eval, eval, eval, eval, isAlpha, isAlphaNumeric, isEmptyString, isEqualTo, isLongerThan, isLowerCase, isMissing, isNotEqualTo, isNotMissing, isNumeric, isShorterThan, isUpperCase, lengthEquals, matchesRegex, startsWith, startsWith

Methods inherited from interface tech.tablesaw.columns.strings.StringMapFunctions
abbreviate, capitalize, commonPrefix, commonSuffix, concatenate, concatenate, countTokens, distance, format, join, length, lowerCase, padEnd, padStart, parseDouble, parseFloat, parseInt, repeat, replaceAll, replaceAll, replaceFirst, substring, substring, tokenizeAndRemoveDuplicates, tokenizeAndSort, tokenizeAndSort, tokens, trim, uniqueTokens, upperCase

Methods inherited from interface tech.tablesaw.columns.strings.StringReduceUtils
appendAll, appendAll

Methods inherited from interface tech.tablesaw.columns.Column
allMatch, anyMatch, columnWidth, count, count, mapInto, max, min, name, noneMatch, print, reduce, reduce, rolling, set, setMissingTo, title, type

Methods inherited from interface java.lang.Iterable
forEach, spliterator

Methods inherited from interface java.util.Comparator
comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

- Method Detail
  - valueIsMissing
```
public static boolean valueIsMissing(String string)
```
  - appendMissing
```
public StringColumn appendMissing()
```
    Description copied from interface: Column
    
    Appends a missing value appropriate to the column
  - create
```
public static StringColumn create(String name)
```
  - create
```
public static StringColumn create(String name,
                                  String[] strings)
```
  - create
```
public static StringColumn create(String name,
                                  List<String> strings)
```
  - createInternal
```
public static StringColumn createInternal(String name,
                                          DictionaryMap map)
```
  - create
```
public static StringColumn create(String name,
                                  int size)
```
  - create
```
public static StringColumn create(String name,
                                  Stream<String> stream)
```
  - isMissing
```
public boolean isMissing(int rowNumber)
```
  - emptyCopy
```
public StringColumn emptyCopy()
```
    Description copied from interface: Column
    
    Returns a copy of the receiver with no data. The column name and type are the same.
    
    Specified by:
    
    emptyCopy in interface Column<String>
    
    Specified by:
    
    emptyCopy in class AbstractColumn<String>
    
    Returns:
    
    a empty copy of Column
  - emptyCopy
```
public StringColumn emptyCopy(int rowSize)
```
    Description copied from interface: Column
    
    Returns an empty copy of the receiver, with its internal storage initialized to the given row size.
    
    Parameters:
    
    rowSize - the initial row size
    
    Returns:
    
    a Column
  - sortAscending
```
public void sortAscending()
```
  - sortDescending
```
public void sortDescending()
```
  - size
```
public int size()
```
    Returns the number of elements (a.k.a. rows or cells) in the column
    
    Returns:
    
    size as int
  - get
```
public String get(int rowIndex)
```
    Returns the value at rowIndex in this column. The index is zero-based.
    
    Parameters:
    
    rowIndex - index of the row
    
    Returns:
    
    value as String
    
    Throws:
    
    IndexOutOfBoundsException - if the given rowIndex is not in the column
  - asList
```
public List<String> asList()
```
    Returns a List<String> representation of all the values in this column
    NOTE: Unless you really need a string consider using the column itself for large datasets as it uses much less memory
    
    Returns:
    
    values as a list of String.
  - summary
```
public Table summary()
```
  - countByCategory
```
public Table countByCategory()
```
  - clear
```
public void clear()
```
  - lead
```
public StringColumn lead(int n)
```
    Description copied from interface: Column
    
    Returns a column of the same type as the receiver, containing the receivers values offset -n For example if you lead a column containing 2, 3, 4 by 1, you get a column containing 3, 4, NA.
  - lag
```
public StringColumn lag(int n)
```
    Description copied from interface: Column
    
    Returns a column of the same type and size as the receiver, containing the receivers values offset by n.
    For example if you lag a column containing 2, 3, 4 by 1, you get a column containing NA, 2, 3
  - set
```
public StringColumn set(Selection rowSelection,
                        String newValue)
```
    Conditionally update this column, replacing current values with newValue for all rows where the current value matches the selection criteria
    Examples: myCatColumn.set(myCatColumn.isEqualTo("Cat"), "Dog"); // no more cats myCatColumn.set(myCatColumn.valueIsMissing(), "Fox"); // no more missing values
  - set
```
public StringColumn set(int rowIndex,
                        String stringValue)
```
  - countUnique
```
public int countUnique()
```
    Description copied from interface: Column
    
    Returns the count of unique values in this column.
    
    Returns:
    
    unique values as int
  - contains
```
public boolean contains(String aString)
```
    Returns true if this column contains a cell with the given string, and false otherwise
    
    Parameters:
    
    aString - the value to look for
    
    Returns:
    
    true if contains, false otherwise
  - setMissing
```
public Column<String> setMissing(int i)
```
  - addAll
```
public StringColumn addAll(List<String> stringValues)
```
    Add all the strings in the list to this column
    
    Parameters:
    
    stringValues - a list of values
  - appendCell
```
public StringColumn appendCell(String object)
```
  - appendCell
```
public StringColumn appendCell(String object,
                               AbstractColumnParser<?> parser)
```
  - rowComparator
```
public it.unimi.dsi.fastutil.ints.IntComparator rowComparator()
```
  - isEmpty
```
public boolean isEmpty()
```
    Description copied from interface: Column
    
    Returns true if the column has no data
    
    Returns:
    
    true if empty, false if not
  - isEqualTo
```
public Selection isEqualTo(String string)
```
  - isNotEqualTo
```
public Selection isNotEqualTo(String string)
```
  - getDummies
```
public List<BooleanColumn> getDummies()
```
    Returns a list of boolean columns suitable for use as dummy variables in, for example, regression analysis, select a column of categorical data must be encoded as a list of columns, such that each column represents a single category and indicates whether it is present (1) or not present (0)
    
    Returns:
    
    a list of BooleanColumn
  - unique
```
public StringColumn unique()
```
    Returns a new Column containing all the unique values in this column
    
    Returns:
    
    a column with unique values.
  - asDoubleColumn
```
public DoubleColumn asDoubleColumn()
```
  - where
```
public StringColumn where(Selection selection)
```
  - copy
```
public StringColumn copy()
```
    Description copied from interface: Column
    
    Returns a deep copy of the receiver
    
    Returns:
    
    a Column
  - append
```
public StringColumn append(Column<String> column)
```
  - countMissing
```
public int countMissing()
```
    Returns the count of missing values in this column
    
    Returns:
    
    missing values as int
  - removeMissing
```
public StringColumn removeMissing()
```
  - iterator
```
public Iterator<String> iterator()
```
  - asSet
```
public Set<String> asSet()
```
  - asBytes
```
public byte[] asBytes(int rowNumber)
```
    Returns the contents of the cell at rowNumber as a byte[]
    
    Parameters:
    
    rowNumber - index of the row
    
    Returns:
    
    content as byte[]
  - getDouble
```
public double getDouble(int i)
```
  - asDoubleArray
```
public double[] asDoubleArray()
```
  - append
```
public StringColumn append(String value)
```
    Added for naming consistency with all other columns
  - appendObj
```
public StringColumn appendObj(Object obj)
```
  - isIn
```
public Selection isIn(String... strings)
```
  - isIn
```
public Selection isIn(Collection<String> strings)
```
  - isNotIn
```
public Selection isNotIn(String... strings)
```
  - isNotIn
```
public Selection isNotIn(Collection<String> strings)
```
  - firstIndexOf
```
public int firstIndexOf(String value)
```
  - countOccurrences
```
public int countOccurrences(String value)
```
  - asObjectArray
```
public String[] asObjectArray()
```
  - setName
```
public StringColumn setName(String name)
```
    Description copied from interface: Column
    
    Sets the columns name to the given string
    
    Specified by:
    
    setName in interface Column<String>
    
    Overrides:
    
    setName in class AbstractColumn<String>
    
    Parameters:
    
    name - The new name MUST be unique for any table containing this column
    
    Returns:
    
    this Column to allow method chaining
  - filter
```
public StringColumn filter(Predicate<? super String> test)
```
    Description copied from interface: Column
    
    Returns a new Column of the same type with only those rows satisfying the predicate
    
    Parameters:
    
    test - the predicate
    
    Returns:
    
    a new Column of the same type with only those rows satisfying the predicate
  - subset
```
public StringColumn subset(int[] rows)
```
  - sorted
```
public StringColumn sorted(Comparator<? super String> comp)
```
    Description copied from interface: Column
    
    Returns a new Column of the same type sorted according to the provided Comparator
    
    Parameters:
    
    comp - the Comparator
    
    Returns:
    
    a sorted Column
  - map
```
public StringColumn map(Function<? super String,? extends String> fun)
```
    Description copied from interface: Column
    
    Maps the function across all rows, appending the results to a new Column of the same type
    
    Parameters:
    
    fun - function to map
    
    Returns:
    
    the Column with the results
  - min
```
public StringColumn min(Column<String> other)
```
    Description copied from interface: Column
    
    Returns a column containing the element-wise min between this column and other column
    TODO(lwhite) Override in column subtypes for better performance
  - max
```
public StringColumn max(Column<String> other)
```
    Description copied from interface: Column
    
    Returns a column containing the element-wise min between this column and other column
    TODO(lwhite) Override in column subtypes for better performance
  - set
```
public StringColumn set(Selection condition,
                        Column<String> other)
```
    Description copied from interface: Column
    
    Updates this column where values matching the selection are replaced with the corresponding value from the given column
  - first
```
public StringColumn first(int numRows)
```
  - last
```
public StringColumn last(int numRows)
```
  - inRange
```
public StringColumn inRange(int start,
                            int end)
```
    Description copied from interface: Column
    
    Returns a column containing the rows in this column beginning with start inclusive, and ending with end exclusive
  - sampleN
```
public StringColumn sampleN(int n)
```
    Description copied from interface: Column
    
    Returns a column containing a random sample of the values in this column
    
    Parameters:
    
    n - the number of values to select
    
    Returns:
    
    A column of the same type as the receiver
  - sampleX
```
public StringColumn sampleX(double proportion)
```
    Description copied from interface: Column
    
    Returns a table consisting of randomly selected values from this column. The sample size is based on the given proportion of the total number of cells in this column
    
    Parameters:
    
    proportion - The proportion to go in the sample
  - asStringColumn
```
public StringColumn asStringColumn()
```
    Description copied from interface: Column
    
    Returns a StringColumn consisting of the (unformatted) String representation of this column values
    
    Specified by:
    
    asStringColumn in interface Column<String>
    
    Overrides:
    
    asStringColumn in class AbstractColumn<String>
    
    Returns:
    
    a StringColumn built using the column Column.getUnformattedString(int) method
  - asTextColumn
```
public TextColumn asTextColumn()
```
  - getLookupTable
```
public LookupTableWrapper getLookupTable()
```
    For tablesaw internal use only

Class StringColumn

Field Summary

Fields inherited from class tech.tablesaw.columns.AbstractColumn

Method Summary

Methods inherited from class tech.tablesaw.columns.strings.AbstractStringColumn

Methods inherited from class tech.tablesaw.columns.AbstractColumn

Methods inherited from class java.lang.Object

Methods inherited from interface tech.tablesaw.columns.strings.StringFilters

Methods inherited from interface tech.tablesaw.columns.strings.StringMapFunctions

Methods inherited from interface tech.tablesaw.columns.strings.StringReduceUtils

Methods inherited from interface tech.tablesaw.columns.Column

Methods inherited from interface java.lang.Iterable

Methods inherited from interface java.util.Comparator

Method Detail

valueIsMissing

appendMissing

create

create

create

createInternal

create

create

isMissing

emptyCopy

emptyCopy

sortAscending

sortDescending

size

get

asList

summary

countByCategory

clear

lead

lag

set

set

countUnique

contains

setMissing

addAll

appendCell

appendCell

rowComparator

isEmpty

isEqualTo

isNotEqualTo

getDummies

unique

asDoubleColumn

where

copy

append

countMissing

removeMissing

iterator

asSet

asBytes

getDouble

asDoubleArray

append

appendObj

isIn

isIn

isNotIn

isNotIn

firstIndexOf

countOccurrences

asObjectArray

setName

filter

subset

sorted

map

min

max

set

first

last

inRange