Package ai.djl.ndarray

Class NDArrayAdapter

java.lang.Object
ai.djl.ndarray.NDArrayAdapter
All Implemented Interfaces:
BytesSupplier, NDArray, NDResource, AutoCloseable
public abstract class NDArrayAdapter extends Object implements NDArray
A base implementation of the NDArray that does nothing. This can be used for overriding the NDArray with only part of the interface implemented.

This interface should only be used for the NDArray implementations that do not plan to implement a large portion of the interface. For the ones that do, they should directly implement NDArray so that the unsupported operations are better highlighted in the code.

  • Field Details

    • manager

      protected NDManager manager

    • alternativeManager

      protected NDManager alternativeManager

    • shape

      protected Shape shape

    • dataType

      protected DataType dataType

    • name

      protected String name

    • isClosed

      protected boolean isClosed

    • uid

      protected String uid

  • Constructor Details

  • Method Details

    • getManager

      public NDManager getManager()
      Returns the NDManager that manages this.
      Specified by:
      getManager in interface NDResource
      Returns:
      the NDManager that manages this.

    • attach

      public void attach(NDManager manager)
      Attaches this NDResource to the specified NDManager.

      Attached resource will be closed when the NDManager is closed.

      Specified by:
      attach in interface NDResource
      Parameters:
      manager - the NDManager to be attached to

    • tempAttach

      public void tempAttach(NDManager manager)
      Temporarily attaches this NDResource to the specified NDManager.

      Attached resource will be returned to the original manager when the NDManager is closed.

      Specified by:
      tempAttach in interface NDResource
      Parameters:
      manager - the NDManager to be attached to

    • getSparseFormat

      public SparseFormat getSparseFormat()
      Returns the SparseFormat of this NDArray.
      Specified by:
      getSparseFormat in interface NDArray
      Returns:
      the SparseFormat of this NDArray

    • getName

      public String getName()
      Returns the name of this NDArray.
      Specified by:
      getName in interface NDArray
      Returns:
      the name of this NDArray

    • setName

      public void setName(String name)
      Sets name of this NDArray.
      Specified by:
      setName in interface NDArray
      Parameters:
      name - the name of this NDArray

    • getUid

      public String getUid()
      Returns unique identifier of this NDArray.
      Specified by:
      getUid in interface NDArray
      Returns:
      unique identifier of this NDArray

    • getDevice

      public Device getDevice()
      Returns the Device of this NDArray.

      Device class contains the information where this NDArray stored in memory, like CPU/GPU.

      Specified by:
      getDevice in interface NDArray
      Returns:
      the Device of this NDArray

    • getDataType

      public DataType getDataType()
      Returns the DataType of this NDArray.

      DataType is a definition of the precision level of the NDArray. All values inside the same NDArray would have the same DataType.

      Specified by:
      getDataType in interface NDArray
      Returns:
      the DataType of this NDArray

    • getShape

      public Shape getShape()
      Returns the Shape of this NDArray.

      Shape defines how this NDArray is represented multi-dimensionally.

      Specified by:
      getShape in interface NDArray
      Returns:
      the Shape of this NDArray

    • toDevice

      public NDArray toDevice(Device device, boolean copy)
      Moves this NDArray to a different Device.
      Specified by:
      toDevice in interface NDArray
      Parameters:
      device - the Device to be set
      copy - set true if you want to return a copy of the Existing NDArray
      Returns:
      the result NDArray with the new Device

    • toType

      public NDArray toType(DataType dataType, boolean copy)
      Converts this NDArray to a different DataType.
      Specified by:
      toType in interface NDArray
      Parameters:
      dataType - the DataType to be set
      copy - set true if you want to return a copy of the Existing NDArray
      Returns:
      the result NDArray with the new DataType

    • setRequiresGradient

      public void setRequiresGradient(boolean requiresGrad)
      Attaches a gradient NDArray to this NDArray and marks it so GradientCollector.backward(NDArray) can compute the gradient with respect to it.
      Specified by:
      setRequiresGradient in interface NDArray
      Parameters:
      requiresGrad - if NDArray requires gradient or not

    • getGradient

      public NDArray getGradient()
      Returns the gradient NDArray attached to this NDArray.
      Specified by:
      getGradient in interface NDArray
      Returns:
      the gradient NDArray

    • hasGradient

      public boolean hasGradient()
      Returns true if the gradient calculation is required for this NDArray.
      Specified by:
      hasGradient in interface NDArray
      Returns:
      true if the gradient calculation is required for this NDArray else false

    • stopGradient

      public NDArray stopGradient()
      Returns an NDArray equal to this that stop gradient propagation through it.
      Specified by:
      stopGradient in interface NDArray
      Returns:
      an NDArray equal to this that stops gradient propagation through it

    • toStringArray

      public String[] toStringArray(Charset charset)
      Converts this NDArray to a String array with the specified charset.

      This method is only applicable to the String typed NDArray and not for printing purpose

      Specified by:
      toStringArray in interface NDArray
      Parameters:
      charset - to charset for the string
      Returns:
      Array of Strings

    • gather

      public NDArray gather(NDArray index, int axis)
      Returns a partial NDArray pointed by the indexed array. 
       out[i][j][k] = input[index[i][j][k]][j][k] # if axis == 0
 out[i][j][k] = input[i][index[i][j][k]][k] # if axis == 1
 out[i][j][k] = input[i][j][index[i][j][k]] # if axis == 2
      Specified by:
      gather in interface NDArray
      Parameters:
      index - picks the elements of an NDArray to the same position as index
      axis - the entries of index are indices of axis
      Returns:
      the partial NDArray of the same shape as index

    • gatherNd

      public NDArray gatherNd(NDArray index)
      Returns a partial NDArray pointed by the indexed array. 
       Given NDArray arr and NDArray idx. idx is the following structure:
 \( idx = [ idx[0, ...], idx[1, ...],..., idx[indexingDepth,...] ] \)
 corresponding to x, y, z index, i.e. [idx_x, idx_y, idx_z, ...].

      So indexingDepth smaller than or equal to data.shape[0] If indexingDepth is smaller than data.shape[0], for instance, data.shape[0]=3, i.e. x,y,z but indexingDepth = 2, i.e. [idx_x, idx_y], then the tail co-rank = data.shape[0] - indexingDepth will be kept.

      With it, the output shape = idx_y.shape appended by data.shape[indexingDepth:] mx.symbol.gather_nd

      Specified by:
      gatherNd in interface NDArray
      Parameters:
      index - picks the elements of an NDArray to the same position as index
      Returns:
      the partial NDArray of the same shape as index

    • take

      public NDArray take(NDManager manager, NDArray index)
      Returns a partial NDArray pointed by index according to linear indexing, and the of output is of the same shape as index.
      Specified by:
      take in interface NDArray
      Parameters:
      manager - the manager used to create the arrays
      index - picks the elements of an NDArray and output to the same entry as in index
      Returns:
      the partial NDArray of the same shape as index

    • put

      public NDArray put(NDArray index, NDArray value)
      Sets the entries of NDArray pointed by index, according to linear indexing, to be the numbers in value.

      Value has to be of the same shape as index.

      Specified by:
      put in interface NDArray
      Parameters:
      index - select the entries of an NDArray
      value - numbers to assign to the indexed entries
      Returns:
      the NDArray with updated values

    • scatter

      public NDArray scatter(NDArray index, NDArray value, int axis)
      Writes all values from the tensor value into self at the indices specified in the index tensor. 
       This is the reverse operation of the manner described in gather().

 self[index[i][j][k]][j][k] = value[i][j][k] # if axis == 0
 self[i][index[i][j][k]][k] = value[i][j][k] # if axis == 1
 self[i][j][index[i][j][k]] = value[i][j][k] # if axis == 2
      torch.Tensor.scatter_
      Specified by:
      scatter in interface NDArray
      Parameters:
      index - the indices of elements to scatter, can be either empty or of the same dimensionality as value. When empty, the operation returns self unchanged
      value - the source element(s) to scatter
      axis - the axis along which to index
      Returns:
      the NDArray with updated values

    • get

      public NDArray get(NDIndex index)
      Returns a partial NDArray.
      Specified by:
      get in interface NDArray
      Parameters:
      index - the section of this NDArray to return
      Returns:
      the partial NDArray

    • set

      public void set(Buffer buffer)
      Sets this NDArray value from Buffer.
      Specified by:
      set in interface NDArray
      Parameters:
      buffer - the input buffered data

    • set

      public void set(NDIndex index, NDArray value)
      Sets the specified index in this NDArray with the given values.
      Specified by:
      set in interface NDArray
      Parameters:
      index - the locations to update
      value - the value to replace with. Can broadcast if given smaller dimensions than the index

    • set

      public void set(NDIndex index, Number value)
      Sets the specified index in this NDArray with the given value.
      Specified by:
      set in interface NDArray
      Parameters:
      index - the locations to update
      value - the value to replace with

    • set

      public void set(NDIndex index, Function<NDArray,NDArray> function)
      Sets the specific index by a function.
      Specified by:
      set in interface NDArray
      Parameters:
      index - the locations to update
      function - the function to change the value

    • set

      public void set(NDArray index, Number value)
      Sets the NDArray by boolean mask or integer index.
      Specified by:
      set in interface NDArray
      Parameters:
      index - the boolean or integer NDArray that indicates what to get
      value - the value to replace with

    • setScalar

      public void setScalar(NDIndex index, Number value)
      Sets the specified scalar in this NDArray with the given value.
      Specified by:
      setScalar in interface NDArray
      Parameters:
      index - the single index to update
      value - the value to replace with

    • booleanMask

      public NDArray booleanMask(NDArray index, int axis)
      Returns portion of this NDArray given the index boolean NDArray along given axis.
      Specified by:
      booleanMask in interface NDArray
      Parameters:
      index - boolean NDArray mask
      axis - an integer that represents the axis of NDArray to mask from
      Returns:
      the result NDArray

    • sequenceMask

      public NDArray sequenceMask(NDArray sequenceLength, float value)
      Sets all elements outside the sequence to a constant value.

      This function takes an n-dimensional input array of the form [batch_size, max_sequence_length, ....] and returns an array of the same shape. Parameter sequenceLength is used to handle variable-length sequences. sequence_length should be an input array of positive ints of dimension [batch_size].

      Specified by:
      sequenceMask in interface NDArray
      Parameters:
      sequenceLength - used to handle variable-length sequences
      value - the constant value to be set
      Returns:
      the result NDArray

    • sequenceMask

      public NDArray sequenceMask(NDArray sequenceLength)
      Sets all elements outside the sequence to 0.

      This function takes an n-dimensional input array of the form [batch_size, max_sequence_length, ....] and returns an array of the same shape. Parameter sequenceLength is used to handle variable-length sequences. sequence_length should be an input array of positive ints of dimension [batch_size].

      Specified by:
      sequenceMask in interface NDArray
      Parameters:
      sequenceLength - used to handle variable-length sequences
      Returns:
      the result NDArray

    • contentEquals

      public boolean contentEquals(Number number)
      Returns true if all elements in this NDArray are equal to the Number.

      Examples 

       jshell> NDArray array = manager.ones(new Shape(2, 3));
 jshell> array.contentEquals(1); // return true instead of boolean NDArray
 true
      Specified by:
      contentEquals in interface NDArray
      Parameters:
      number - the number to compare
      Returns:
      the boolean result

    • contentEquals

      public boolean contentEquals(NDArray other)
      Returns true if all elements in this NDArray are equal to the other NDArray.

      Examples 

       jshell> NDArray array1 = manager.arange(6f).reshape(2, 3);
 jshell> NDArray array2 = manager.create(new float[] {0f, 1f, 2f, 3f, 4f, 5f}, new Shape(2, 3));
 jshell> array1.contentEquals(array2); // return true instead of boolean NDArray
 true
      Specified by:
      contentEquals in interface NDArray
      Parameters:
      other - the other NDArray to compare
      Returns:
      the boolean result

    • eq

      public NDArray eq(Number n)
      Returns the boolean NDArray for element-wise "Equals" comparison.

      Examples 

       jshell> NDArray array = manager.ones(new Shape(1));
 jshell> array.eq(1);
 ND: (1) cpu() boolean
 [ true]
      Specified by:
      eq in interface NDArray
      Parameters:
      n - the number to compare
      Returns:
      the boolean NDArray for element-wise "Equals" comparison

    • eq

      public NDArray eq(NDArray other)
      Returns the boolean NDArray for element-wise "Equals" comparison.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {0f, 1f, 3f});
 jshell> NDArray array2 = manager.arange(3f);
 jshell> array1.eq(array2);
 ND: (3) cpu() boolean
 [ true,  true, false]
      Specified by:
      eq in interface NDArray
      Parameters:
      other - the NDArray to compare
      Returns:
      the boolean NDArray for element-wise "Equals" comparison

    • neq

      public NDArray neq(Number n)
      Returns the boolean NDArray for element-wise "Not equals" comparison.

      Examples 

       jshell> NDArray array = manager.arange(4f).reshape(2, 2);
 jshell> array.neq(1);
 ND: (2, 2) cpu() boolean
 [[ true, false],
  [ true,  true],
 ]
      Specified by:
      neq in interface NDArray
      Parameters:
      n - the number to compare
      Returns:
      the boolean NDArray for element-wise "Not equals" comparison

    • neq

      public NDArray neq(NDArray other)
      Returns the boolean NDArray for element-wise "Not equals" comparison.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {1f, 2f});
 jshell> NDArray array2 = manager.create(new float[] {1f, 3f});
 jshell> array1.neq(array2);
 ND: (2) cpu() boolean
 [false,  true]
 jshell> NDArray array1 = manager.create(new float[] {1f, 2f});
 jshell> NDArray array2 = manager.create(new float[] {1f, 3f, 1f, 4f}, new Shape(2, 2));
 jshell> array1.neq(array2); // broadcasting
 ND: (2, 2) cpu() boolean
 [[false,  true],
  [false,  true],
 ]
      Specified by:
      neq in interface NDArray
      Parameters:
      other - the NDArray to compare
      Returns:
      the boolean NDArray for element-wise "Not equals" comparison

    • gt

      public NDArray gt(Number n)
      Returns the boolean NDArray for element-wise "Greater" comparison.

      Examples 

       jshell> NDArray array = manager.create(new float[] {4f, 2f});
 jshell> array.gt(2f);
 ND: (2) cpu() boolean
 [ true, false]
      Specified by:
      gt in interface NDArray
      Parameters:
      n - the number to compare
      Returns:
      the boolean NDArray for element-wise "Greater" comparison

    • gt

      public NDArray gt(NDArray other)
      Returns the boolean NDArray for element-wise "Greater Than" comparison.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {4f, 2f});
 jshell> NDArray array2 = manager.create(new float[] {2f, 2f});
 jshell> array1.neq(array2);
 ND: (2) cpu() boolean
 [ true, false]
      Specified by:
      gt in interface NDArray
      Parameters:
      other - the NDArray to compare
      Returns:
      the boolean NDArray for element-wis "Greater Than" comparison

    • gte

      public NDArray gte(Number n)
      Returns the boolean NDArray for element-wise "Greater or equals" comparison. 
       jshell> NDArray array = manager.create(new float[] {4f, 2f});
 jshell> array.gte(2f);
 ND: (2) cpu() boolean
 [ true, true]
      Specified by:
      gte in interface NDArray
      Parameters:
      n - the number to compare
      Returns:
      the boolean NDArray for element-wise "Greater or equals" comparison

    • gte

      public NDArray gte(NDArray other)
      Returns the boolean NDArray for element-wise "Greater or equals" comparison.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {4f, 2f});
 jshell> NDArray array2 = manager.create(new float[] {2f, 2f});
 jshell> array1.gte(array2);
 ND: (2) cpu() boolean
 [ true, true]
      Specified by:
      gte in interface NDArray
      Parameters:
      other - the number to compare
      Returns:
      the boolean NDArray for "Greater or equals" comparison

    • lt

      public NDArray lt(Number n)
      Returns the boolean NDArray for element-wise "Less" comparison.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array.lt(2f);
 ND: (2) cpu() boolean
 [ true, false]
      Specified by:
      lt in interface NDArray
      Parameters:
      n - the number to compare
      Returns:
      the boolean NDArray for element-wise "Less" comparison

    • lt

      public NDArray lt(NDArray other)
      Returns the boolean NDArray for element-wise "Less" comparison.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {1f, 2f});
 jshell> NDArray array2 = manager.create(new float[] {2f, 2f});
 jshell> array1.lt(array2);
 ND: (2) cpu() boolean
 [ true, false]
      Specified by:
      lt in interface NDArray
      Parameters:
      other - the NDArray to compare
      Returns:
      the boolean NDArray for element-wise "Less" comparison

    • lte

      public NDArray lte(Number n)
      Returns the boolean NDArray for element-wise "Less or equals" comparison.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array.lte(2f);
 ND: (2) cpu() boolean
 [ true, true]
      Specified by:
      lte in interface NDArray
      Parameters:
      n - the number to compare
      Returns:
      the boolean NDArray for element-wise "Less or equals" comparison

    • lte

      public NDArray lte(NDArray other)
      Returns the boolean NDArray for element-wise "Less or equals" comparison.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {1f, 2f});
 jshell> NDArray array2 = manager.create(new float[] {2f, 2f});
 jshell> array1.lte(array2);
 ND: (2) cpu() boolean
 [ true, true]
      Specified by:
      lte in interface NDArray
      Parameters:
      other - the NDArray to compare
      Returns:
      the boolean NDArray for element-wise "Less or equals" comparison

    • add

      public NDArray add(Number n)
      Adds a number to this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array.add(2f);
 ND: (2) cpu() float32
 [3., 4.]
      Specified by:
      add in interface NDArray
      Parameters:
      n - the number to add
      Returns:
      the result NDArray

    • add

      public NDArray add(NDArray other)
      Adds other NDArrays to this NDArray element-wise.

      The shapes of this NDArray and other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.arange(9f).reshape(3, 3);
 jshell> NDArray array2 = manager.arange(3f);
 jshell> array1.add(array2); // broadcasting
 ND: (3, 3) cpu() float32
 [[ 0.,  2.,  4.],
  [ 3.,  5.,  7.],
  [ 6.,  8., 10.],
 ]
      Specified by:
      add in interface NDArray
      Parameters:
      other - the other NDArrays to add
      Returns:
      the result NDArray

    • sub

      public NDArray sub(Number n)
      Subtracts a number from this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array.sub(2f);
 ND: (2) cpu() float32
 [-1.,  0.]
      Specified by:
      sub in interface NDArray
      Parameters:
      n - the number to subtract from
      Returns:
      the result NDArray

    • sub

      public NDArray sub(NDArray other)
      Subtracts the other NDArray from this NDArray element-wise.

      The shapes of this NDArray and other NDArrays must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.arange(9).reshape(3, 3);
 jshell> NDArray array2 = manager.arange(3);
 jshell> array1.sub(array2); // broadcasting
 ND: (3, 3) cpu() float32
 [[0., 0., 0.],
  [3., 3., 3.],
  [6., 6., 6.],
 ]
      Specified by:
      sub in interface NDArray
      Parameters:
      other - the other NDArray to subtract from
      Returns:
      the result NDArray

    • mul

      public NDArray mul(Number n)
      Multiplies this NDArray by a number element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array.mul(3f);
 ND: (2) cpu() float32
 [3., 6.]
      Specified by:
      mul in interface NDArray
      Parameters:
      n - the number to multiply by
      Returns:
      the result NDArray

    • mul

      public NDArray mul(NDArray other)
      Multiplies this NDArray by other NDArrays element-wise.

      The shapes of this NDArray and other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.arange(9f).reshape(3, 3);
 jshell> NDArray array2 = manager.arange(3f);
 jshell> array1.mul(array2); // broadcasting
 ND: (3, 3) cpu() float32
 [[ 0.,  1.,  4.],
  [ 0.,  4., 10.],
  [ 0.,  7., 16.],
 ]
      Specified by:
      mul in interface NDArray
      Parameters:
      other - the other NDArrays to multiply by
      Returns:
      the result NDArray

    • div

      public NDArray div(Number n)
      Divides this NDArray by a number element-wise.

      Examples 

       jshell> NDArray array = manager.arange(5f);
 jshell> array.div(4f);
 ND: (5) cpu() float32
 [0.  , 0.25, 0.5 , 0.75, 1.  ]
      Specified by:
      div in interface NDArray
      Parameters:
      n - the number to divide by
      Returns:
      the result NDArray

    • div

      public NDArray div(NDArray other)
      Divides this NDArray by the other NDArray element-wise.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.arange(9f).reshape(3, 3);
 jshell> NDArray array2 = manager.ones(new Shape(3)).mul(10);
 jshell> array1.div(array2); // broadcasting
 ND: (3, 3) cpu() float32
 [[0. , 0.1, 0.2],
  [0.3, 0.4, 0.5],
  [0.6, 0.7, 0.8],
 ]
      Specified by:
      div in interface NDArray
      Parameters:
      other - the other NDArray to divide by
      Returns:
      the result NDArray

    • mod

      public NDArray mod(Number n)
      Returns element-wise remainder of division.

      Examples 

       jshell> NDArray array = manager.arange(7f);
 jshell> array.mod(5f);
 ND: (7) cpu() float32
 [0., 1., 2., 3., 4., 0., 1.]
      Specified by:
      mod in interface NDArray
      Parameters:
      n - the divisor number
      Returns:
      the result NDArray

    • mod

      public NDArray mod(NDArray other)
      Returns element-wise remainder of division.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {4f, 7f});
 jshell> NDArray array2 = manager.create(new float[] {2f, 3f});
 jshell> array1.mod(array2);
 ND: (2) cpu() float32
 [0., 1.]
      Specified by:
      mod in interface NDArray
      Parameters:
      other - the divisor NDArray
      Returns:
      the result NDArray

    • pow

      public NDArray pow(Number n)
      Takes the power of this NDArray with a number element-wise.

      Examples 

       jshell> NDArray array = manager.arange(5f);
 jshell> array.pow(4f);
 ND: (6) cpu() float32
 [  0.,   1.,   8.,  27.,  64., 125.]
      Specified by:
      pow in interface NDArray
      Parameters:
      n - the number to take the power with
      Returns:
      the result NDArray

    • pow

      public NDArray pow(NDArray other)
      Takes the power of this NDArray with the other NDArray element-wise.

      Examples 

       jshell> NDArray array1 = manager.arange(6f).reshape(3, 2);
 jshell> NDArray array2 = manager.create(new float[] {2f, 3f});
 jshell> array1.pow(array2); // broadcasting
 ND: (3, 2) cpu() float32
 [[  0.,   1.],
  [  4.,  27.],
  [ 16., 125.],
 ]
      Specified by:
      pow in interface NDArray
      Parameters:
      other - the other NDArray to take the power with
      Returns:
      the result NDArray

    • addi

      public NDArray addi(Number n)
      Adds a number to this NDArray element-wise in place.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array.addi(2f);
 ND: (2) cpu() float32
 [3., 4.]
 jshell> array;
 ND: (2) cpu() float32
 [3., 4.]
      Specified by:
      addi in interface NDArray
      Parameters:
      n - the number to add
      Returns:
      the result NDArray

    • addi

      public NDArray addi(NDArray other)
      Adds other NDArrays to this NDArray element-wise in place.

      The shapes of this NDArray and other NDArrays must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {1f, 2f});
 jshell> NDArray array2 = manager.create(new float[] {3f, 4f});
 jshell> array1.addi(array2);
 ND: (2) cpu() float32
 [4., 6.]
 jshell> array;
 ND: (2) cpu() float32
 [4., 6.]
      Specified by:
      addi in interface NDArray
      Parameters:
      other - the other NDArrays to add
      Returns:
      the result NDArray

    • subi

      public NDArray subi(Number n)
      Subtracts a number from this NDArray element-wise in place.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array.subi(2f);
 ND: (2) cpu() float32
 [-1.,  0.]
 jshell> array;
 ND: (2) cpu() float32
 [-1.,  0.]
      Specified by:
      subi in interface NDArray
      Parameters:
      n - the number to subtract
      Returns:
      the result NDArray

    • subi

      public NDArray subi(NDArray other)
      Subtracts the other NDArray from this NDArray element-wise in place.

      The shapes of this NDArray and other NDArrays must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.arange(9f).reshape(3, 3);
 jshell> NDArray array2 = manager.arange(3f);
 jshell> array1.subi(array2); // broadcasting
 ND: (3, 3) cpu() float32
 [[0., 0., 0.],
  [3., 3., 3.],
  [6., 6., 6.],
 ]
 jshell> array1;
 [[0., 0., 0.],
  [3., 3., 3.],
  [6., 6., 6.],
 ]
      Specified by:
      subi in interface NDArray
      Parameters:
      other - the other NDArray to subtract from
      Returns:
      the result NDArray

    • muli

      public NDArray muli(Number n)
      Multiplies this NDArray by a number element-wise in place.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array.muli(3f);
 ND: (2) cpu() float32
 [3., 6.]
 jshell> array;
 ND: (2) cpu() float32
 [3., 6.]
      Specified by:
      muli in interface NDArray
      Parameters:
      n - the number to multiply by
      Returns:
      the result NDArray

    • muli

      public NDArray muli(NDArray other)
      Multiplies this NDArray by other NDArray element-wise in place.

      The shapes of this NDArray and other NDArrays must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.arange(9f).reshape(3, 3);
 jshell> NDArray array2 = manager.arange(3f);
 jshell> array1.muli(array2); // broadcasting
 ND: (3, 3) cpu() float32
 [[ 0.,  1.,  4.],
  [ 0.,  4., 10.],
  [ 0.,  7., 16.],
 ]
 jshell> array1;
 ND: (3, 3) cpu() float32
 [[ 0.,  1.,  4.],
  [ 0.,  4., 10.],
  [ 0.,  7., 16.],
 ]
      Specified by:
      muli in interface NDArray
      Parameters:
      other - the other NDArrays to multiply with
      Returns:
      the result NDArray

    • divi

      public NDArray divi(Number n)
      Divides this NDArray by a number element-wise in place.

      Examples 

       jshell> NDArray array = manager.arange(5f);
 jshell> array.divi(4f);
 ND: (5) cpu() float32
 [0.  , 0.25, 0.5 , 0.75, 1.  ]
 jshell> array;
 ND: (5) cpu() float32
 [0.  , 0.25, 0.5 , 0.75, 1.  ]
      Specified by:
      divi in interface NDArray
      Parameters:
      n - the number to divide values by
      Returns:
      the array after applying division operation

    • divi

      public NDArray divi(NDArray other)
      Divides this NDArray by the other NDArray element-wise in place.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.arange(9f).reshape(3, 3);
 jshell> NDArray array2 = manager.ones(new Shape(3)).mul(10);
 jshell> array1.divi(array2); // broadcasting
 ND: (3, 3) cpu() float32
 [[0. , 0.1, 0.2],
  [0.3, 0.4, 0.5],
  [0.6, 0.7, 0.8],
 ]
 jshell> array1;
 [[0. , 0.1, 0.2],
  [0.3, 0.4, 0.5],
  [0.6, 0.7, 0.8],
 ]
      Specified by:
      divi in interface NDArray
      Parameters:
      other - the other NDArray to divide by
      Returns:
      the result of the divide

    • modi

      public NDArray modi(Number n)
      Returns element-wise remainder of division in place.

      Examples 

       jshell> NDArray array = manager.arange(7f);
 jshell> array.modi(5f);
 ND: (7) cpu() float32
 [0., 1., 2., 3., 4., 0., 1.]
 jshell> array;
 ND: (7) cpu() float32
 [0., 1., 2., 3., 4., 0., 1.]
      Specified by:
      modi in interface NDArray
      Parameters:
      n - the divisor number
      Returns:
      the result NDArray

    • modi

      public NDArray modi(NDArray other)
      Returns in place element-wise remainder of division in place.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {4f, 7f});
 jshell> NDArray array2 = manager.create(new float[] {2f, 3f});
 jshell> array1.modi(array2);
 ND: (2) cpu() float32
 [0., 1.]
 jshell> array1;
 ND: (2) cpu() float32
 [0., 1.]
      Specified by:
      modi in interface NDArray
      Parameters:
      other - the divisor NDArray
      Returns:
      the result of the divide

    • powi

      public NDArray powi(Number n)
      Takes the power of this NDArray with a number element-wise in place.

      Examples 

       jshell> NDArray array = manager.arange(5f);
 jshell> array.powi(4f);
 ND: (6) cpu() float32
 [  0.,   1.,   8.,  27.,  64., 125.]
 jshell> array;
 ND: (6) cpu() float32
 [  0.,   1.,   8.,  27.,  64., 125.]
      Specified by:
      powi in interface NDArray
      Parameters:
      n - the number to raise the power to
      Returns:
      the result NDArray

    • powi

      public NDArray powi(NDArray other)
      Takes the power of this NDArray with the other NDArray element-wise in place.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.arange(6f).reshape(3, 2);
 jshell> NDArray array2 = manager.create(new float[] {2f, 3f});
 jshell> array1.powi(array2); // broadcasting
 ND: (3, 2) cpu() float32
 [[  0.,   1.],
  [  4.,  27.],
  [ 16., 125.],
 ]
 jshell> array1;
 ND: (3, 2) cpu() float32
 [[  0.,   1.],
  [  4.,  27.],
  [ 16., 125.],
 ]
      Specified by:
      powi in interface NDArray
      Parameters:
      other - the other NDArray to take the power with
      Returns:
      the result NDArray

    • sign

      public NDArray sign()
      Returns the element-wise sign.
      Specified by:
      sign in interface NDArray
      Returns:
      the result NDArray

    • signi

      public NDArray signi()
      Returns the element-wise sign in-place.
      Specified by:
      signi in interface NDArray
      Returns:
      the result NDArray

    • maximum

      public NDArray maximum(Number n)
      Returns the maximum of this NDArray and a number element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {2f, 3f, 4f});
 jshell> array.maximum(3f);
 ND: (3) cpu() float32
 [3., 3., 4.]
      Specified by:
      maximum in interface NDArray
      Parameters:
      n - the number to be compared
      Returns:
      the maximum of this NDArray and a number element-wise

    • maximum

      public NDArray maximum(NDArray other)
      Returns the maximum of this NDArray and the other NDArray element-wise.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {2f, 3f, 4f});
 jshell> NDArray array2 = manager.create(new float[] {1f, 5f, 2f});
 jshell> array1.maximum(array2);
 ND: (3) cpu() float32
 [2., 5., 4.]
 jshell> NDArray array1 = manager.eye(2);
 jshell> NDArray array2 = manager.create(new float[] {0.5f, 2f});
 jshell> array1.maximum(array2); // broadcasting
 ND: (2, 2) cpu() float32
 [[1. , 2. ],
  [0.5, 2. ],
 ]
      Specified by:
      maximum in interface NDArray
      Parameters:
      other - the NDArray to be compared
      Returns:
      the maximum of this NDArray and the other NDArray element-wise

    • minimum

      public NDArray minimum(Number n)
      Returns the minimum of this NDArray and a number element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {2f, 3f, 4f});
 jshell> array.minimum(3f);
 ND: (3) cpu() float32
 [2., 3., 3.]
      Specified by:
      minimum in interface NDArray
      Parameters:
      n - the number to be compared
      Returns:
      the minimum of this NDArray and a number element-wise

    • minimum

      public NDArray minimum(NDArray other)
      Returns the minimum of this NDArray and the other NDArray element-wise.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {2f, 3f, 4f});
 jshell> NDArray array2 = manager.create(new float[] {1f, 5f, 2f});
 jshell> array1.minimum(array2);
 ND: (3) cpu() float32
 [1., 3., 2.]
 jshell> NDArray array1 = manager.eye(2);
 jshell> NDArray array2 = manager.create(new float[] {0.5f, 2f});
 jshell> array1.minimum(array2); // broadcasting
 ND: (2, 2) cpu() float32
 [[0.5, 0. ],
  [0. , 1. ],
 ]
      Specified by:
      minimum in interface NDArray
      Parameters:
      other - the NDArray to be compared
      Returns:
      the minimum of this NDArray and the other NDArray element-wise

    • neg

      public NDArray neg()
      Returns the numerical negative NDArray element-wise. 
       jshell> NDArray array = manager.arange(5f);
 jshell> array.neg();
 ND: (5) cpu() float32
 [-0., -1., -2., -3., -4.]
      Specified by:
      neg in interface NDArray
      Returns:
      the result NDArray

    • negi

      public NDArray negi()
      Returns the numerical negative NDArray element-wise in place. 
       jshell> NDArray array = manager.arange(5f);
 jshell> array.negi();
 jshell> array;
 ND: (5) cpu() float32
 [-0., -1., -2., -3., -4.]
      Specified by:
      negi in interface NDArray
      Returns:
      the result NDArray

    • abs

      public NDArray abs()
      Returns the absolute value of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {-1f, -2f});
 jshell> array.abs();
 ND: (2) cpu() float32
 [1., 2.]
      Specified by:
      abs in interface NDArray
      Returns:
      the result NDArray

    • square

      public NDArray square()
      Returns the square of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {2f, -3f});
 jshell> array.square();
 ND: (2) cpu() float32
 [4., 9.]
      Specified by:
      square in interface NDArray
      Returns:
      the result NDArray

    • sqrt

      public NDArray sqrt()
      Returns the square root of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {4f});
 jshell> array.sqrt();
 ND: (1) cpu() float32
 [2., ]
      Specified by:
      sqrt in interface NDArray
      Returns:
      the result NDArray

    • cbrt

      public NDArray cbrt()
      Returns the cube-root of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 8f, 27f});
 jshell> array.cbrt();
 ND: (3) cpu() float32
 [1., 2., 3.]
      Specified by:
      cbrt in interface NDArray
      Returns:
      the result NDArray

    • floor

      public NDArray floor()
      Returns the floor of this NDArray element-wise.

      The floor of the scalar x is the largest integer i, such that i <= x.

      Examples 

       jshell> NDArray array = manager.create(new float[] {-1.7f, -1.5f, -0.2f, 0.2f, 1.5f, 1.7f, 2.0f});
 jshell> array.floor();
 ND: (7) cpu() float32
 [-2., -2., -1.,  0.,  1.,  1.,  2.]
      Specified by:
      floor in interface NDArray
      Returns:
      the result NDArray

    • ceil

      public NDArray ceil()
      Returns the ceiling of this NDArray element-wise.

      The ceil of the scalar x is the smallest integer i, such that i >= x.

      Examples 

       jshell> NDArray array = manager.create(new float[] {-1.7f, -1.5f, -0.2f, 0.2f, 1.5f, 1.7f, 2.0f});
 jshell> array.ceil();
 ND: (7) cpu() float32
 [-1., -1., -0.,  1.,  2.,  2.,  2.]
      Specified by:
      ceil in interface NDArray
      Returns:
      the result NDArray

    • round

      public NDArray round()
      Returns the round of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {-1.7f, -1.5f, -0.2f, 0.2f, 1.5f, 1.7f, 2.0f});
 jshell> array.round();
 ND: (7) cpu() float32
 [-2., -2., -0.,  0.,  2.,  2.,  2.]
      Specified by:
      round in interface NDArray
      Returns:
      the result NDArray

    • trunc

      public NDArray trunc()
      Returns the truncated value of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {-1.7f, -1.5f, -0.2f, 0.2f, 1.5f, 1.7f, 2.0f});
 jshell> array.trunc();
 ND: (7) cpu() float32
 [-1., -1., -0.,  0.,  1.,  1.,  2.]
      Specified by:
      trunc in interface NDArray
      Returns:
      the result NDArray

    • exp

      public NDArray exp()
      Returns the exponential value of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 2.5f});
 jshell> array.exp();
 ND: (2) cpu() float32
 [ 1.    , 12.1825]
      Specified by:
      exp in interface NDArray
      Returns:
      the result NDArray

    • gammaln

      public NDArray gammaln()
      Return the log of the absolute value of the gamma function of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0.5f, 1f, 1.5f});
 jshell> array.gammaln();
 ND: (2) cpu() float32
 [ 0.5724,  0.0000, -0.1208]
      Specified by:
      gammaln in interface NDArray
      Returns:
      the result NDArray

    • log

      public NDArray log()
      Returns the natural logarithmic value of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 2.5f});
 jshell> array.log();
 ND: (2) cpu() float32
 [  -inf, 0.9163]
      Specified by:
      log in interface NDArray
      Returns:
      the result NDArray

    • log10

      public NDArray log10()
      Returns the base 10 logarithm of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1000f, 1f, 150f});
 jshell> array.log10();
 ND: (3) cpu() float32
 [3.    , 0.    , 2.1761]
      Specified by:
      log10 in interface NDArray
      Returns:
      the result NDArray

    • log2

      public NDArray log2()
      Returns the base 2 logarithm of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new float[] {8, 1f, 5f});
 jshell> array.log2();
 ND: (3) cpu() float32
 [3.    , 0.    , 2.3219]
      Specified by:
      log2 in interface NDArray
      Returns:
      the result NDArray

    • sin

      public NDArray sin()
      Returns the trigonometric sine of this NDArray element-wise.

      The input should be in radians (2 Pi radians equals 360 degrees).

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 30f, 45f, 60f, 90f});
 jshell> array = array.mul(Math.PI).div(180f);
 jshell> array.sin();
 ND: (5) cpu() float32
 [0.    , 0.5   , 0.7071, 0.866 , 1.    ]
      Specified by:
      sin in interface NDArray
      Returns:
      the result NDArray

    • cos

      public NDArray cos()
      Returns the trigonometric cosine of this NDArray element-wise.

      The input should be in radians (2 Pi radians equals 360 degrees).

      Examples 

       jshell> NDArray array = manager.create(new double[] {0, Math.PI/2, Math.PI});
 jshell> array.cos();
 ND: (3) cpu() float64
 [  1.0000000e+00,   6.1232340e-17,  -1.0000000e+00],
      Specified by:
      cos in interface NDArray
      Returns:
      the result NDArray

    • tan

      public NDArray tan()
      Returns the trigonometric tangent of this NDArray element-wise.

      The input should be in radians (2 Pi radians equals 360 degrees).

      Examples 

       jshell> NDArray array = manager.create(new double[] {-Math.PI, Math.PI/2, Math.PI});
 jshell> array.tan();
 ND: (3) cpu() float64
 [  1.2246468e-16,   1.6331239e+16,  -1.2246468e-16],
      Specified by:
      tan in interface NDArray
      Returns:
      the result NDArray

    • asin

      public NDArray asin()
      Returns the inverse trigonometric sine of this NDArray element-wise.

      The input should be in the range [-1, 1]. The output is in the closed interval of [-Pi/2, Pi/2].

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, -1f, 0f});
 jshell> array.asin();
 ND: (3) cpu() float64
 [ 1.5708, -1.5708,  0.    ]
      Specified by:
      asin in interface NDArray
      Returns:
      the result NDArray

    • acos

      public NDArray acos()
      Returns the inverse trigonometric cosine of this NDArray element-wise.

      The input should be in the range [-1, 1]. The output is in the closed interval of [-Pi/2, Pi/2].

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, -1f});
 jshell> array.acos();
 ND: (2) cpu() float64
 [0.    , 3.1416]
      Specified by:
      acos in interface NDArray
      Returns:
      the result NDArray

    • atan

      public NDArray atan()
      Returns the inverse trigonometric tangent of this NDArray element-wise.

      The input should be in the range [-1, 1]. The output is in the closed interval of [-Pi/2, Pi/2].

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f});
 jshell> array.atan();
 ND: (2) cpu() float64
 [0.    , 0.7854]
      Specified by:
      atan in interface NDArray
      Returns:
      the result NDArray

    • atan2

      public NDArray atan2(NDArray other)
      Returns the element-wise arc-tangent of this/other choosing the quadrant correctly.

      Examples 

       jshell> NDArray x = manager.create(new float[] {0f, 1f});
 jshell> NDArray y = manager.create(new float[] {0f, -6f});
 jshell> x.atan2(y);
 ND: (2) cpu() float64
 [0.    , 2.9764]
      Specified by:
      atan2 in interface NDArray
      Parameters:
      other - The other NDArray
      Returns:
      the result NDArray

    • sinh

      public NDArray sinh()
      Returns the hyperbolic sine of this NDArray element-wise.

      sinh(x)=0.5*(exp(x) - exp(-x))

      Examples 

       jshell> NDArray array = manager.create(new double[] {0, Math.PI});
 jshell> array.sinh();
 ND: (2) cpu() float64
 [ 0.    , 11.5487]
      Specified by:
      sinh in interface NDArray
      Returns:
      the result NDArray

    • cosh

      public NDArray cosh()
      Returns the hyperbolic cosine of this NDArray element-wise.

      cosh(x)=0.5*(exp(x)+exp(-x))

      Examples 

       jshell> NDArray array = manager.create(new double[] {0, Math.PI});
 jshell> array.cosh();
 ND: (2) cpu() float64
 [ 1.    , 11.592 ]
      Specified by:
      cosh in interface NDArray
      Returns:
      the result NDArray

    • tanh

      public NDArray tanh()
      Returns the hyperbolic tangent of this NDArray element-wise.

      tanh(x)=sinh(x)/cosh(x)

      Examples 

       jshell> NDArray array = manager.create(new double[] {0, Math.PI});
 jshell> array.tanh();
 ND: (2) cpu() float64
 [0.    , 0.9963]
      Specified by:
      tanh in interface NDArray
      Returns:
      the result NDArray

    • asinh

      public NDArray asinh()
      Returns the inverse hyperbolic sine of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new double[] {Math.E, 10});
 jshell> array.asinh();
 ND: (2) cpu() float64
 [1.7254, 2.9982]
      Specified by:
      asinh in interface NDArray
      Returns:
      the result NDArray

    • acosh

      public NDArray acosh()
      Returns the inverse hyperbolic cosine of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new double[] {Math.E, 10});
 jshell> array.acosh();
 ND: (2) cpu() float64
 [1.6575, 2.9932]
      Specified by:
      acosh in interface NDArray
      Returns:
      the result NDArray

    • atanh

      public NDArray atanh()
      Returns the inverse hyperbolic tangent of this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new double[] {0, -0.5});
 jshell> array.atanh();
 ND: (2) cpu() float64
 [ 0.    , -0.5493]
      Specified by:
      atanh in interface NDArray
      Returns:
      the result NDArray

    • toDegrees

      public NDArray toDegrees()
      Converts this NDArray from radians to degrees element-wise.

      Examples 

       jshell> NDArray array = manager.arange(6f).mul(Math.PI / 3);
 jshell> array.toDegrees();
 ND: (6) cpu() float32
 [  0.,  60., 120., 180., 240., 300.]
      Specified by:
      toDegrees in interface NDArray
      Returns:
      the result NDArray

    • toRadians

      public NDArray toRadians()
      Converts this NDArray from degrees to radians element-wise.

      Examples 

       jshell> NDArray array = manager.arange(6f).mul(60);
 jshell> array.toRadians();
 ND: (6) cpu() float32
 [0.    , 1.0472, 2.0944, 3.1416, 4.1888, 5.236 ]
      Specified by:
      toRadians in interface NDArray
      Returns:
      the result NDArray

    • max

      public NDArray max()
      Returns the maximum of this NDArray.

      Examples 

       jshell> NDArray array = manager.arange(4f).reshape(2,2);
 jshell> array;
 ND: (2, 2) cpu() float32
 [[0., 1.],
  [2., 3.],
 ]
 jshell> array.max(); // Maximum of the flattened array
 ND: () cpu() float32
 3.
 jshell> array.max().getFloat() // Use getFloat() to get native float
 3.0
      Specified by:
      max in interface NDArray
      Returns:
      the maximum of this NDArray

    • max

      public NDArray max(int[] axes, boolean keepDims)
      Returns the maximum of this NDArray along given axes.

      Examples 

       jshell> NDArray array = manager.arange(4f).reshape(2,2);
 jshell> array;
 ND: (2, 2) cpu() float32
 [[0., 1.],
  [2., 3.],
 ]
 jshell> array.max(new int[]{0}, true); // Maximum along the first axis and keep dimension
 ND: (1, 2) cpu() float32
 [[2., 3.],
 ]
 jshell> array.max(new int[]{1}, true); // Maximum along the second axis and keep dimension
 ND: (2, 1) cpu() float32
 [[1.],
  [3.],
 ]
      Specified by:
      max in interface NDArray
      Parameters:
      axes - the axes along which to operate
      keepDims - true to keep the specified axes as size 1 in the output array, false to squeeze the values out of the output array.
      Returns:
      the maximum of this NDArray

    • min

      public NDArray min()
      Returns the minimum of this NDArray.

      Examples 

       jshell> NDArray array = manager.arange(4f).reshape(2,2);
 jshell> array;
 ND: (2, 2) cpu() float32
 [[0., 1.],
  [2., 3.],
 ]
 jshell> array.min(); // Minimum of the flattened array
 ND: () cpu() float32
 0.
 jshell> array.min().getFloat(); // Use getFloat() to get native float
 0.0
      Specified by:
      min in interface NDArray
      Returns:
      the minimum of this NDArray

    • min

      public NDArray min(int[] axes, boolean keepDims)
      Returns the minimum of this NDArray along given axes.

      Examples 

       jshell> NDArray array = manager.arange(4f).reshape(2,2);
 jshell> array
 ND: (2, 2) cpu() float32
 [[0., 1.],
  [2., 3.],
 ]
 jshell> array.min(new int[]{0}, true) // Minimum along the first axis and keep dimension
 ND: (1, 2) cpu() float32
 [[0., 1.],
 ]
 jshell> array.min(new int[]{1}, true) // Minimum along the second axis and keep dimension
 ND: (2, 1) cpu() float32
 [[0.],
  [2.],
 ]
      Specified by:
      min in interface NDArray
      Parameters:
      axes - the axes along which to operate
      keepDims - true to keep the specified axes as size 1 in the output array, false to squeeze the values out of the output array
      Returns:
      the minimum of this NDArray

    • sum

      public NDArray sum()
      Returns the sum of this NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0.5f, 1.5f});
 jshell> array.sum();
 ND: () cpu() float32
 2.
 jshell> array.sum().getFloat(); // Use getFloat() to get native float
 2.0
 jshell> NDArray array = manager.create(new float[] {0f, 1f, 0f, 5f}, new Shape(2, 2));
 jshell> array.sum();
 ND: () cpu() float32
 6.
      Specified by:
      sum in interface NDArray
      Returns:
      the sum of this NDArray

    • sum

      public NDArray sum(int[] axes, boolean keepDims)
      Returns the sum of this NDArray along given axes.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 0f, 5f}, new Shape(2, 2));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[0., 1.],
  [0., 5.],
 ]
 jshell> array.sum(new int[] {0}, true);
 ND: (1, 2) cpu() float32
 [[0., 6.],
 ]
 jshell> array.sum(new int[] {1}, true);
 ND: (2, 2) cpu() float32
 [[0., 1.],
  [0., 5.],
 ]
      Specified by:
      sum in interface NDArray
      Parameters:
      axes - the axes along which to operate
      keepDims - true to keep the specified axes as size 1 in the output array, false to squeeze the values out of the output array
      Returns:
      the sum of this NDArray

    • cumProd

      public NDArray cumProd(int axis)
      Returns the cumulative product of elements of input in the dimension dim. For example, if input is a vector of size N, the result will also be a vector of size N, with elements. [x1, x1 * x2, x1 * x2 *x3 ...]
      Specified by:
      cumProd in interface NDArray
      Parameters:
      axis - the axis along which to operate
      Returns:
      the cumulative product of this

    • cumProd

      public NDArray cumProd(int axis, DataType dataType)
      Returns the cumulative product of elements of input in the dimension dim. For example, if input is a vector of size N, the result will also be a vector of size N, with elements. [x1, x1 * x2, x1 * x2 *x3 ...]
      Specified by:
      cumProd in interface NDArray
      Parameters:
      axis - the axis along which to operate
      dataType - the datatype of the output
      Returns:
      the cumulative product of this

    • prod

      public NDArray prod()
      Returns the product of this NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {2f, 3f});
 jshell> array.prod();
 ND: () cpu() float32
 6.
 jshell> array.prod().getFloat(); // Use getFloat to get native float
 6.0
 jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array.prod();
 ND: () cpu() float32
 24.
      Specified by:
      prod in interface NDArray
      Returns:
      the product of this NDArray

    • prod

      public NDArray prod(int[] axes, boolean keepDims)
      Returns the product of this NDArray elements over the given axes.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[1., 2.],
  [3., 4.],
 ]
 jshell> array.prod(new int[] {0}, true);
 ND: (1, 2) cpu() float32
 [[3., 8.],
 ]
 jshell> array.prod(new int[] {1}, true);
 ND: (2, 1) cpu() float32
 [[ 2.],
  [12.],
 ]
      Specified by:
      prod in interface NDArray
      Parameters:
      axes - the axes along which to operate
      keepDims - true to keep the specified axes as size 1 in the output array, false to squeeze the values out of the output array
      Returns:
      the product of this NDArray

    • mean

      public NDArray mean()
      Returns the average of this NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {2f, 3f});
 jshell> array.mean();
 ND: () cpu() float32
 2.5
 jshell> array.mean().getFloat(); // Use getFloat() to get native float
 2.5
 jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array.mean();
 ND: () cpu() float32
 2.5
      Specified by:
      mean in interface NDArray
      Returns:
      the average of this NDArray

    • mean

      public NDArray mean(int[] axes, boolean keepDims)
      Returns the average of this NDArray along given axes.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[1., 2.],
  [3., 4.],
 ]
 jshell> array.mean(new int[] {0}, true);
 ND: (1, 2) cpu() float32
 [[2., 3.],
 ]
 jshell> array.mean(new int[] {1}, true);
 ND: (2, 1) cpu() float32
 [[1.5],
  [3.5],
 ]
      Specified by:
      mean in interface NDArray
      Parameters:
      axes - the axes along which to operate
      keepDims - true to keep the specified axes as size 1 in the output array, false to squeeze the values out of the output array
      Returns:
      the average of this NDArray

    • normalize

      public NDArray normalize(double p, long dim, double eps)
      Performs Lp normalization of the array over specified dimension.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1, 2, 3, 4, 5, 6}, new Shape(2, 3));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[1., 2., 3.],
  [4., 5., 6.],
 ]
 jshell> array.normalize(2, 1, 1e-12);
 ND: (2, 3) cpu() float32
 [[0.2673, 0.5345, 0.8018],
  [0.4558, 0.5698, 0.6838],
 ]
      Specified by:
      normalize in interface NDArray
      Parameters:
      p - the exponent value in the norm formulation
      dim - the dimension to reduce
      eps - the small value to avoid division by zero
      Returns:
      the normalized NDArray

    • rotate90

      public NDArray rotate90(int times, int[] axes)
      Rotates an array by 90 degrees in the plane specified by axes.

      Rotation direction is from the first towards the second axis.

      Specified by:
      rotate90 in interface NDArray
      Parameters:
      times - Number of times the array is rotated by 90 degrees.
      axes - The array is rotated in the plane defined by the axes. Axes must be different.
      Returns:
      the rotated NDArray

    • trace

      public NDArray trace(int offset, int axis1, int axis2)
      Returns the sum along diagonals of this NDArray.

      If this NDArray is 2-D, the sum along its diagonal with the given offset is returned, i.e., the sum of elements a[i,i+offset] for all i. If this NDArray has more than two dimensions, then the axes specified by axis1 and axis2 are used to determine the 2-D sub-arrays whose traces are returned. The Shape of the resulting array is the same as this NDArray with axis1 and axis2 removed.

      Examples 

       jshell> NDArray array = manager.arange(8f).reshape(2, 2, 2);
 jshell> array;
 ND: (2, 2, 2) cpu() float32
 [[[0., 1.],
   [2., 3.],
  ],
  [[4., 5.],
   [6., 7.],
  ],
 ]
 jshell> array.trace(1,1,2);
 ND: (2) cpu() float32
 [1., 5.]
      Specified by:
      trace in interface NDArray
      Parameters:
      offset - offset of the diagonal from the main diagonal. Can be both positive and negative.
      axis1 - axes to be used as the first axis of the 2-D sub-arrays from which the diagonals should be taken
      axis2 - axes to be used as the second axis of the 2-D sub-arrays from which the diagonals should be taken
      Returns:
      the sum along diagonals of this NDArray

    • split

      public NDList split(long sections, int axis)
      Splits this NDArray into multiple subNDArrays given sections along the given axis.

      Examples 

       jshell> NDArray array = manager.arange(18f).reshape(2, 9);
 jshell> array;
 ND: (2, 9) cpu() float32
 [[ 0.,  1.,  2.,  3.,  4.,  5.,  6.,  7.,  8.],
  [ 9., 10., 11., 12., 13., 14., 15., 16., 17.],
 ]
 jshell> array.split(3, 1).forEach(System.out::println);
 ND: (2, 3) cpu() float32
 [[ 0.,  1.,  2.],
  [ 9., 10., 11.],
 ]

 ND: (2, 3) cpu() float32
 [[ 3.,  4.,  5.],
  [12., 13., 14.],
 ]

 ND: (2, 3) cpu() float32
 [[ 6.,  7.,  8.],
  [15., 16., 17.],
 ]
      Specified by:
      split in interface NDArray
      Parameters:
      sections - this NDArray will be divided into N (sections) equal arrays along axis
      axis - the axis to split along
      Returns:
      an NDList with numOutputs NDArrays with Shape (this.shape.axis /= axis)

    • split

      public NDList split(long[] indices, int axis)
      Splits this NDArray into multiple sub-NDArrays given indices along given axis.

      Examples 

       jshell> NDArray array = manager.arange(18f).reshape(2, 9);
 jshell> array;
 ND: (2, 9) cpu() float32
 [[ 0.,  1.,  2.,  3.,  4.,  5.,  6.,  7.,  8.],
  [ 9., 10., 11., 12., 13., 14., 15., 16., 17.],
 ]
 jshell> array.split(new int[] {2,4,5}, 1).forEach(System.out::println);
 ND: (2, 2) cpu() float32
 [[ 0.,  1.],
  [ 9., 10.],
 ]

 ND: (2, 2) cpu() float32
 [[ 2.,  3.],
  [11., 12.],
 ]

 ND: (2, 1) cpu() float32
 [[ 4.],
  [13.],
 ]

 ND: (2, 4) cpu() float32
 [[ 5.,  6.,  7.,  8.],
  [14., 15., 16., 17.],
 ]
      Specified by:
      split in interface NDArray
      Parameters:
      indices - the entries indicate where along axis this NDArray is split. If an index exceeds the dimension of this NDArray along axis, an empty sub-array is returned correspondingly
      axis - the axis to split along
      Returns:
      an NDList with numOutputs NDArrays with Shape (this.shape.axis /= axis)

    • flatten

      public NDArray flatten()
      Flattens this NDArray into a 1-D NDArray in row-major order.

      To flatten in column-major order, first transpose this NDArray

      Examples 

       jshell> NDArray array = manager.create(new float[]{1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array.flatten();
 ND: (4) cpu() float32
 [1., 2., 3., 4.]
      Specified by:
      flatten in interface NDArray
      Returns:
      a 1-D NDArray of equal size

    • flatten

      public NDArray flatten(int startDim, int endDim)
      Flattens this NDArray into a partially flatten NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[]{1f, 2f, 3f, 4f, 5f, 6f, 7f, 8f}, new Shape(2, 2, 2));
 jshell> array.flatten(0, 1);
 ND: (4) cpu() float32
 [[1., 2], [3., 4.], [5., 6.], [7., 8.]]
      Specified by:
      flatten in interface NDArray
      Parameters:
      startDim - the first dim to flatten, inclusive
      endDim - the last dim to flatten, inclusive
      Returns:
      a partially fallen NDArray

    • fft

      public NDArray fft(long length, long axis)
      Computes the one-dimensional discrete Fourier Transform.
      Specified by:
      fft in interface NDArray
      Parameters:
      length - Length of the transformed axis of the output.
      axis - Axis over which to compute the FFT.
      Returns:
      The truncated or zero-padded input, transformed along the axis indicated by axis, or the last one if axis is not specified.

    • ifft

      public NDArray ifft(long length, long axis)
      Computes the one dimensional inverse discrete Fourier transform.
      Specified by:
      ifft in interface NDArray
      Parameters:
      length - Length of the transformed axis of the output.
      axis - Axis over which to compute the IFFT.
      Returns:
      The truncated or zero-padded input, transformed along the axis indicated by axis, or the last one if axis is not specified.

    • rfft

      public NDArray rfft(long length, long axis)
      Computes the one dimensional Fourier transform of real-valued input.
      Specified by:
      rfft in interface NDArray
      Parameters:
      length - Length of the transformed axis of the output.
      axis - Axis over which to compute the FFT.
      Returns:
      The truncated or transformed along the axis indicated by axis, or the last one if axis is not specified.

    • irfft

      public NDArray irfft(long length, long axis)
      Computes the one dimensional inverse Fourier transform of real-valued input.
      Specified by:
      irfft in interface NDArray
      Parameters:
      length - Length of the transformed axis of the output.
      axis - Axis over which to compute the IRFFT.
      Returns:
      The truncated or transformed along the axis indicated by axis, or the last one if axis is not specified.

    • stft

      public NDArray stft(long nFft, long hopLength, boolean center, NDArray window, boolean normalize, boolean returnComplex)
      Computes the Short Time Fourier Transform (STFT).
      Specified by:
      stft in interface NDArray
      Parameters:
      nFft - size of Fourier transform
      hopLength - the distance between neighboring sliding window frames. Default can be: floor(n_fft / 4)
      center - whether to pad input on both sides.
      window - Desired window to use. Recommend for HanningWindow
      normalize - controls whether to return the normalized STFT results
      returnComplex - whether to return a complex tensor, or a real tensor with an extra last dimension for the real and imaginary components.
      Returns:
      A NDArray containing the STFT result with shape described above

    • fft2

      public NDArray fft2(long[] sizes, long[] axes)
      Computes the two-dimensional Discrete Fourier Transform.
      Specified by:
      fft2 in interface NDArray
      Parameters:
      sizes - Sizes of the transformed axes of the output. Will be zero-padded or trimmed to this size.
      axes - Axes over which to compute the 2D-FFT.
      Returns:
      The truncated or zero-padded input, transformed along the axes.

    • pad

      public NDArray pad(Shape padding, double value)
      Pads this NDArray with the given Shape.

      Examples 

       NDArray array = manager.zeros(3, 3, 4, 2);
 array.pad(new Shape(1, 1), 0); # pad last dim by 1 on each side
 array.getShape() => (3, 3, 4, 4)
      Specified by:
      pad in interface NDArray
      Parameters:
      padding - the padding shape, must be even
      Returns:
      a padded NDArray

    • ifft2

      public NDArray ifft2(long[] sizes, long[] axes)
      Computes the two-dimensional inverse Discrete Fourier Transform.
      Specified by:
      ifft2 in interface NDArray
      Parameters:
      sizes - Sizes of the transformed axes of the output. Will be zero-padded or trimmed to this size.
      axes - Axes over which to compute the 2D-Inverse-FFT.
      Returns:
      The truncated or zero-padded input, transformed along the axes.

    • reshape

      public NDArray reshape(Shape shape)
      Reshapes this NDArray to the given Shape.

      You can reshape it to match another NDArray by calling a.reshape(b.getShape())

      Examples 

       jshell> NDArray array = manager.arange(6f);
 jshell> array;
 ND: (6) cpu() float32
 [0., 1., 2., 3., 4., 5.]
 jshell> array.reshape(new Shape(2, 3));
 ND: (2, 3) cpu() float32
 [[0., 1., 2.],
  [3., 4., 5.],
 ]
      Specified by:
      reshape in interface NDArray
      Parameters:
      shape - the Shape to reshape into. Must have equal size to the current shape
      Returns:
      a reshaped NDArray

    • expandDims

      public NDArray expandDims(int axis)
      Expands the Shape of a NDArray.

      Inserts a new axis that will appear at the axis position in the expanded NDArray shape.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f});
 jshell> array;
 ND: (2) cpu() float32
 [1., 2.]
 jshell> array.expandDims(0);
 ND: (1, 2) cpu() float32
 [[1., 2.],
 ]
 jshell> array.expandDims(1);
 ND: (2, 1) cpu() float32
 [[1.],
  [2.],
 ]
      Specified by:
      expandDims in interface NDArray
      Parameters:
      axis - the position in the expanded axes where the new axis is placed
      Returns:
      the result NDArray. The number of dimensions is one greater than that of the NDArray

    • squeeze

      public NDArray squeeze(int[] axes)
      Removes singleton dimensions at the given axes.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f}, new Shape(1, 3, 1));
 jshell> array;
 ND: (1, 3, 1) cpu() float32
 [[[0.],
   [1.],
   [2.],
  ],
 ]
 jshell> array.squeeze(new int[] {0, 2});
 ND: (3) cpu() float32
 [0., 1., 2.]
      Specified by:
      squeeze in interface NDArray
      Parameters:
      axes - the axes at which to remove the singleton dimensions
      Returns:
      a result NDArray of same size and data without the axes at part of the shape

    • unique

      public NDList unique(Integer dim, boolean sorted, boolean returnInverse, boolean returnCounts)
      Returns the unique elements of the input tensor.

      Examples 

       jshell> NDArray array = manager.create(new float[] {3f, 1f, 2f, 3f, 1f, 2f, 1f, 3f, 2f}, new Shape(3, 3));
 jshell> array;
 ND: (3, 3) cpu() float32
 [[[3., 1., 2.],
   [3., 1., 2.],
   [1., 3., 2.],
  ],
 ]
 jshell> NDList output = array.unique(0, true, true, true);
 jshell> output.get(0);
 jshell> output.get(1);
 jshell> output.get(2);

 ND: (2, 3) cpu() float32
 [[1., 3., 2.],
  [3., 1., 2.],
 ]

 ND: (3) cpu() int64
 [ 1,  1,  0]

 ND: (2) cpu() int64
 [ 1,  2]
      Specified by:
      unique in interface NDArray
      Parameters:
      dim - the dimension to apply unique
      sorted - whether to sort the unique elements in ascending order before returning as output
      returnInverse - return the indices which, fed into the output unique array as indices, will recover the original array
      returnCounts - return the counts for each unique element
      Returns:
      An NDList containing: output (Tensor): the output list of unique elements or low-rank tensors. inverse_indices (Tensor): (optional) if return_inverse is True, there will be an additional returned tensor (same shape as input) representing the indices for where elements in the original input map to in the output; otherwise, this function will only return a single tensor. counts (Tensor): (optional) if return_counts is True, there will be an additional returned tensor (same shape as output or output.size(dim), if dim was specified) representing the number of occurrences for each unique value or tensor.

    • logicalAnd

      public NDArray logicalAnd(NDArray other)
      Returns the truth value of this NDArray AND the other NDArray element-wise.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.create(new boolean[] {true});
 jshell> NDArray array2 = manager.create(new boolean[] {false});
 jshell> array1.logicalAnd(array2);
 ND: (1) cpu() boolean
 [false]
 jshell> array1 = manager.create(new boolean[] {true, false});
 jshell> array2 = manager.create(new boolean[] {false, false});
 jshell> array1.logicalAnd(array2);
 ND: (2) cpu() boolean
 [false, false]
 
       jshell> NDArray array = manager.arange(5f);
 jshell> array.gt(1).logicalAnd(array.lt(4));
 ND: (5) cpu() boolean
 [false, false,  true,  true, false]
      Specified by:
      logicalAnd in interface NDArray
      Parameters:
      other - the other NDArray to operate on
      Returns:
      the boolean NDArray of the logical AND operation applied to the elements of this NDArray and the other NDArray

    • logicalOr

      public NDArray logicalOr(NDArray other)
      Computes the truth value of this NDArray OR the other NDArray element-wise.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array1 = manager.create(new boolean[] {true});
 jshell> NDArray array2 = manager.create(new boolean[] {false});
 jshell> array1.logicalOr(array2);
 ND: (1) cpu() boolean
 [ true]
 jshell> array1 = manager.create(new boolean[] {true, false});
 jshell> array2 = manager.create(new boolean[] {false, false});
 jshell> array1.logicalOr(array2);
 ND: (2) cpu() boolean
 [ true, false]
 
       jshell> NDArray array = manager.arange(5f);
 jshell> array.lt(1).logicalOr(array.gt(3));
 ND: (5) cpu() boolean
 [ true, false, false, false,  true]
      Specified by:
      logicalOr in interface NDArray
      Parameters:
      other - the other NDArray to operate on
      Returns:
      the boolean NDArray of the logical OR operation applied to the elements of this NDArray and the other NDArray

    • logicalXor

      public NDArray logicalXor(NDArray other)
      Computes the truth value of this NDArray XOR the other NDArray element-wise.

      The shapes of this NDArray and the other NDArray must be broadcastable.

      Examples 

       jshell> NDArray array = manager.create(new boolean[] {true});
 jshell> array1.logicalXor(array2);
 ND: (1) cpu() boolean
 [ true]
 jshell> array1 = manager.create(new boolean[] {true, false});
 jshell> array2 = manager.create(new boolean[] {false, false});
 jshell> array1.logicalXor(array2);
 ND: (2) cpu() boolean
 [ true, false]
 
       jshell> NDArray array = manager.arange(5f);
 jshell> array.lt(1).logicalXor(array.gt(3));
 ND: (5) cpu() boolean
 [ true, false, false, false,  true]
      Specified by:
      logicalXor in interface NDArray
      Parameters:
      other - the other NDArray to operate on
      Returns:
      the boolean NDArray of the logical XOR operation applied to the elements of this NDArray and the other NDArray

    • logicalNot

      public NDArray logicalNot()
      Computes the truth value of NOT this NDArray element-wise.

      Examples 

       jshell> NDArray array = manager.create(new boolean[] {true});
 jshell> array.logicalNot();
 ND: (1) cpu() boolean
 [ false]
 
       jshell> NDArray array = manager.arange(5f);
 jshell> array.lt(1).logicalNot();
 ND: (5) cpu() boolean
 [false, true, true,  true,  true]
      Specified by:
      logicalNot in interface NDArray
      Returns:
      the boolean NDArray

    • argSort

      public NDArray argSort(int axis, boolean ascending)
      Returns the indices that would sort this NDArray given the axis.

      Perform an indirect sort along the given axis. It returns a NDArray of indices of the same Shape as this NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 3f, 2f, 2f}, new Shape(2, 2));
 jshell> array.argSort(0, false);
 ND: (2, 2) cpu() int64
 [[ 1,  0],
  [ 0,  1],
 ]
      Specified by:
      argSort in interface NDArray
      Parameters:
      axis - the axis to sort along
      ascending - whether to sort ascending
      Returns:
      a NDArray of indices corresponding to elements in this NDArray on the axis, the output DataType is always DataType.INT64

    • sort

      public NDArray sort()
      Sorts the flattened NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 4f, 3f, 1f}, new Shape(2, 2));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[1., 4.],
  [3., 1.],
 ]
 jshell> array.sort(); // sort the flattened array
 ND: (2, 2) cpu() float32
 [[1., 4.],
  [1., 3.],
 ]
      Specified by:
      sort in interface NDArray
      Returns:
      the sorted NDArray

    • sort

      public NDArray sort(int axis)
      Sorts the flattened NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 4f, 3f, 1f}, new Shape(2, 2));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[1., 4.],
  [3., 1.],
 ]
 jshell> array.sort(0); // sort along the first axis
 ND: (2, 2) cpu() float32
 [[1., 1.],
  [3., 4.],
 ]
      Specified by:
      sort in interface NDArray
      Parameters:
      axis - the axis to sort along
      Returns:
      the sorted NDArray

    • softmax

      public NDArray softmax(int axis)
      Applies the softmax function along the given axis.
      Specified by:
      softmax in interface NDArray
      Parameters:
      axis - the axis along which to apply
      Returns:
      the result NDArray
      See Also:

    • logSoftmax

      public NDArray logSoftmax(int axis)
      Applies the softmax function followed by a logarithm.

      Mathematically equivalent to calling softmax and then log. This single operator is faster than calling two operators and numerically more stable when computing gradients.

      Specified by:
      logSoftmax in interface NDArray
      Parameters:
      axis - the axis along which to apply
      Returns:
      the result NDArray

    • cumSum

      public NDArray cumSum()
      Returns the cumulative sum of the elements in the flattened NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f, 5f, 6f}, new Shape(2, 3));
 jshell> array;
 ND: (2, 3) cpu() float32
 [[1., 2., 3.],
  [4., 5., 6.],
 ]
 jshell> array.cumSum(); // cumSum on flattened array
 ND: (6) cpu() float32
 [ 1.,  3.,  6., 10., 15., 21.]
      Specified by:
      cumSum in interface NDArray
      Returns:
      the cumulative sum of the elements in the flattened NDArray

    • cumSum

      public NDArray cumSum(int axis)
      Return the cumulative sum of the elements along a given axis.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f, 5f, 6f}, new Shape(2, 3));
 jshell> array;
 ND: (2, 3) cpu() float32
 [[1., 2., 3.],
  [4., 5., 6.],
 ]
 jshell> array.cumSum(0);
 ND: (2, 3) cpu() float32
 [[1., 2., 3.],
  [5., 7., 9.],
 ]
 jshell> array.cumSum(1);
 ND: (2, 3) cpu() float32
 [[ 1.,  3.,  6.],
  [ 4.,  9., 15.],
 ]
      Specified by:
      cumSum in interface NDArray
      Parameters:
      axis - the axis along which the cumulative sum is computed
      Returns:
      the cumulative sum along the specified axis

    • isInfinite

      public NDArray isInfinite()
      Returns the boolean NDArray with value true where this NDArray's entries are infinite, or false where they are not infinite.
      Specified by:
      isInfinite in interface NDArray
      Returns:
      the boolean NDArray with value true if this NDArray's entries are infinite

    • isNaN

      public NDArray isNaN()
      Returns the boolean NDArray with value true where this NDArray's entries are NaN, or false where they are not NaN.

      Examples 

       jshell> NDArray array = manager.create(new float[] {Float.POSITIVE_INFINITY, 0, Float.NaN});
 jshell> array.isNaN();
 ND: (3) cpu() boolean
 [false, false,  true]
      Specified by:
      isNaN in interface NDArray
      Returns:
      the boolean NDArray with value true if this NDArray's NDArray are NaN

    • tile

      public NDArray tile(long repeats)
      Constructs a NDArray by repeating this NDArray the number of times given repeats.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f});
 jshell> array.tile(2);
 ND: (6) cpu() float32
 [0., 1., 2., 0., 1., 2.]
      Specified by:
      tile in interface NDArray
      Parameters:
      repeats - the number of times to repeat for each dimension
      Returns:
      a NDArray that has been tiled

    • tile

      public NDArray tile(int axis, long repeats)
      Constructs a NDArray by repeating this NDArray the number of times given by repeats along given axis.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f});
 jshell> array.tile(1, 2);
 ND: (1, 6) cpu() float32
 [[0., 1., 2., 0., 1., 2.],
 ]
      Specified by:
      tile in interface NDArray
      Parameters:
      axis - the axis to repeat
      repeats - the number of times to repeat for each axis
      Returns:
      a NDArray that has been tiled

    • tile

      public NDArray tile(long[] repeats)
      Constructs a NDArray by repeating this NDArray the number of times given by repeats.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f});
 jshell> array.tile(new long[] {2, 2});
 ND: (2, 6) cpu() float32
 [[0., 1., 2., 0., 1., 2.],
  [0., 1., 2., 0., 1., 2.],
 ]
      Specified by:
      tile in interface NDArray
      Parameters:
      repeats - the number of times to repeat along each axis
      Returns:
      a NDArray that has been tiled

    • tile

      public NDArray tile(Shape desiredShape)
      Constructs a NDArray by repeating this NDArray the number of times to match the desired shape.

      If the desired Shapehas fewer dimensions than this NDArray, it will tile against the last axis.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f});
 jshell> array.tile(new Shape(6));
 ND: (6) cpu() float32
 [0., 1., 2., 0., 1., 2.]
      Specified by:
      tile in interface NDArray
      Parameters:
      desiredShape - the Shapethat should be converted to
      Returns:
      a NDArray that has been tiled

    • repeat

      public NDArray repeat(long repeats)
      Repeats element of this NDArray the number of times given repeats.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f});
 jshell> array.repeat(2);
 ND: (6) cpu() float32
 [0., 0., 1., 1., 2., 2.]
      Specified by:
      repeat in interface NDArray
      Parameters:
      repeats - the number of times to repeat for each axis
      Returns:
      an NDArray that has been repeated

    • repeat

      public NDArray repeat(int axis, long repeats)
      Repeats element of this NDArray the number of times given repeats along given axis.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f, 3f}, new Shape(2, 2));
 jshell> array.repeat(1, 2);
 ND: (6) cpu() float32
 [[0., 0., 1., 1.],
  [2., 2., 3., 3.]]
      Specified by:
      repeat in interface NDArray
      Parameters:
      axis - the axis to repeat
      repeats - the number of times to repeat for each axis
      Returns:
      an NDArray that has been repeated

    • repeat

      public NDArray repeat(long[] repeats)
      Repeats element of this NDArray the number of times given repeats along each axis.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f, 3f}, new Shape(2, 2));
 jshell> array.repeat(new long[] {2, 2});
 ND: (12) cpu() float32
 [0., 0., 0., 0., 1., 1., 1., 1., 2., 2., 2., 2.]
      Specified by:
      repeat in interface NDArray
      Parameters:
      repeats - the number of times to repeat along each axis
      Returns:
      a NDArray that has been repeated

    • repeat

      public NDArray repeat(Shape desiredShape)
      Repeats element of this NDArray to match the desired shape.

      If the desired Shape has fewer dimensions that the array, it will repeat against the last axis.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 1f, 2f, 3f}, new Shape(2, 2));
 jshell> array.repeat(new Shape(4, 4));
 ND: (4, 4) cpu() float32
 [[0., 0., 1., 1.],
  [0., 0., 1., 1.],
  [2., 2., 3., 3.],
  [2., 2., 3., 3.],
 ]
      Specified by:
      repeat in interface NDArray
      Parameters:
      desiredShape - the Shape that should be converted to
      Returns:
      an NDArray that has been repeated

    • dot

      public NDArray dot(NDArray other)
      Dot product of this NDArray and the other NDArray.
      • If both this NDArray and the other NDArray are 1-D NDArrays, it is inner product of vectors (without complex conjugation).
      • If both this NDArray and the other NDArray are 2-D NDArrays, it is matrix multiplication.
      • If either this NDArray or the other NDArray is 0-D NDArray (scalar), it is equivalent to mul.
      • If this NDArray is N-D NDArray and the other NDArray is 1-D NDArray, it is a sum product over the last axis of those.
      • If this NDArray is N-D NDArray and the other NDArray is M-D NDArray(where M>=2), it is a sum product over the last axis of this NDArray and the second-to-last axis of the other NDArray

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {1f, 2f, 3f});
 jshell> NDArray array2 = manager.create(new float[] {4f, 5f, 6f});
 jshell> array1.dot(array2); // inner product
 ND: () cpu() float32
 32.
 jshell> array1 = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array2 = manager.create(new float[] {5f, 6f, 7f, 8f}, new Shape(2, 2));
 jshell> array1.dot(array2); // matrix multiplication
 ND: (2, 2) cpu() float32
 [[19., 22.],
  [43., 50.],
 ]
 jshell> array1 = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array2 = manager.create(5f);
 jshell> array1.dot(array2);
 ND: (2, 2) cpu() float32
 [[ 5., 10.],
  [15., 20.],
 ]
 jshell> array1 = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array2 = manager.create(new float[] {1f, 2f});
 jshell> array1.dot(array2);
 ND: (2) cpu() float32
 [ 5., 11.]
 jshell> array1 = manager.create(new float[] {1f, 2f, 3f, 4f, 5f, 6f, 7f, 8f}, new Shape(2, 2, 2));
 jshell> array2 = manager.create(new float[] {1f, 2f, 3f ,4f}, new Shape(2, 2));
 jshell> array1.dot(array2);
 ND: (2, 2, 2) cpu() float32
 [[[ 7., 10.],
   [15., 22.],
  ],
  [[23., 34.],
   [31., 46.],
  ],
 ]
      Specified by:
      dot in interface NDArray
      Parameters:
      other - the other NDArray to perform dot product with
      Returns:
      the result NDArray

    • matMul

      public NDArray matMul(NDArray other)
      Product matrix of this NDArray and the other NDArray.

      The behavior depends on the arguments in the following way.

      • If both this NDArray and the other NDArray are 2-D NDArrays, they are multiplied like conventional matrices
      • If either this NDArray or the other NDArray is N-D NDArray, N > 2 , it is treated as a stack of matrices residing in the last two indexes and broadcast accordingly.
      • If this NDArray is 1-D NDArray, it is promoted to a matrix by prepending a 1 to its dimensions. After matrix multiplication the prepended 1 is removed.
      • If other NDArray is 1-D NDArray, it is promoted to a matrix by appending a 1 to its dimensions. After matrix multiplication the appended 1 is removed.

      Examples 

       jshell> NDArray array1 = manager.create(new float[] {1f, 0f, 0f, 1f}, new Shape(2, 2));
 jshell> NDArray array2 = manager.create(new float[] {4f, 1f, 2f, 2f}, new Shape(2, 2));
 jshell> array1.matMul(array2); // for 2-D arrays, it is the matrix product
 ND: (2, 2) cpu() float32
 [[4., 1.],
  [2., 2.],
 ]
 jshell> array1 = manager.create(new float[] {1f, 0f, 0f, 1f}, new Shape(2, 2));
 jshell> array2 = manager.create(new float[] {1f, 2f});
 jshell> array1.matMul(array2);
 ND: (2) cpu() float32
 [1., 2.]
 jshell> array1 = manager.create(new float[] {1f, 0f, 0f, 1f}, new Shape(2, 2));
 jshell> array2 = manager.create(new float[] {1f, 2f});
 jshell> array1.matMul(array2);
 ND: (2) cpu() float32
 [1., 2.]
 jshell> array1 = manager.arange(2f * 2f * 4f).reshape(2, 2, 4);
 jshell> array2 = manager.arange(2f * 2f * 4f).reshape(2, 4, 2);
 jshell> array1.matMul(array2).get("0, 1, 1");
 ND: () cpu() float32
 98.
      Specified by:
      matMul in interface NDArray
      Parameters:
      other - the other NDArray to perform matrix product with
      Returns:
      the result NDArray

    • batchMatMul

      public NDArray batchMatMul(NDArray other)
      Batch product matrix of this NDArray and the other NDArray.
      Specified by:
      batchMatMul in interface NDArray
      Parameters:
      other - the other NDArray to perform matrix product with
      Returns:
      the result NDArray

    • xlogy

      public NDArray xlogy(NDArray other)
      Computes this * log(other).
      Specified by:
      xlogy in interface NDArray
      Parameters:
      other - other the other NDArray
      Returns:
      the result NDArray

    • clip

      public NDArray clip(Number min, Number max)
      Clips (limit) the values in this NDArray.

      Given an interval, values outside the interval are clipped to the interval edges. For example, if an interval of [0, 1] is specified, values smaller than 0 become 0, and values larger than 1 become 1.

      Examples 

       jshell> NDArray array = manager.arange(10f);
 jshell> array.clip(1, 8);
 ND: (10) cpu() float32
 [1., 1., 2., 3., 4., 5., 6., 7., 8., 8.]
      Specified by:
      clip in interface NDArray
      Parameters:
      min - the minimum value
      max - the maximum value
      Returns:
      an NDArray with the elements of this NDArray, but where values < min are replaced with min, and those > max with max

    • flip

      public NDArray flip(int... axes)
      Returns the reverse order of elements in an array along the given axis.

      The shape of the array is preserved, but the elements are reordered.

      Specified by:
      flip in interface NDArray
      Parameters:
      axes - the axes to flip on
      Returns:
      the newly flipped array

    • transpose

      public NDArray transpose()
      Returns this NDArray with axes transposed.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f ,3f, 4f}, new Shape(2, 2));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[1., 2.],
  [3., 4.],
 ]
 jshell> array.transpose();
 ND: (2, 2) cpu() float32
 [[1., 3.],
  [2., 4.],
 ]
      Specified by:
      transpose in interface NDArray
      Returns:
      the newly permuted array

    • transpose

      public NDArray transpose(int... axes)
      Returns this NDArray with given axes transposed.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f ,3f, 4f}, new Shape(2, 2));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[1., 2.],
  [3., 4.],
 ]
 jshell> array.transpose(1, 0);
 ND: (2, 2) cpu() float32
 [[1., 3.],
  [2., 4.],
 ]
 jshell> array = manager.arange(8f).reshape(2, 2, 2);
 jshell> array;
 ND: (2, 2, 2) cpu() float32
 [[[0., 1.],
   [2., 3.],
  ],
  [[4., 5.],
   [6., 7.],
  ],
 ]
 jshell> array.transpose(1, 0, 2);
 ND: (2, 2, 2) cpu() float32
 [[[0., 1.],
   [4., 5.],
  ],
  [[2., 3.],
   [6., 7.],
  ],
 ]
      Specified by:
      transpose in interface NDArray
      Parameters:
      axes - the axes to swap to
      Returns:
      the transposed NDArray

    • broadcast

      public NDArray broadcast(Shape shape)
      Broadcasts this NDArray to be the given shape.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f ,3f, 4f}, new Shape(2, 2));
 jshell> array;
 ND: (2, 2) cpu() float32
 [[1., 2.],
  [3., 4.],
 ]
 jshell> array.broadcast(new Shape(2, 2, 2));
 ND: (2, 2, 2) cpu() float32
 [[[1., 2.],
   [3., 4.],
  ],
  [[1., 2.],
   [3., 4.],
  ],
 ]
      Specified by:
      broadcast in interface NDArray
      Parameters:
      shape - the new Shape of this NDArray
      Returns:
      the broadcasted NDArray

    • argMax

      public NDArray argMax()
      Returns the indices of the maximum values into the flattened NDArray.

      Examples 

       jshell> NDArray array = manager.arange(6f).reshape(2, 3);
 jshell> array;
 ND: (2, 3) cpu() float32
 [[0., 1., 2.],
  [3., 4., 5.],
 ]
 jshell> array.argMax();
 ND: () cpu() int64
 5.
      Specified by:
      argMax in interface NDArray
      Returns:
      a NDArray containing indices

    • argMax

      public NDArray argMax(int axis)
      Returns the indices of the maximum values along given axis.

      Examples 

       jshell> NDArray array = manager.arange(6f).reshape(2, 3);
 jshell> array;
 ND: (2, 3) cpu() float32
 [[0., 1., 2.],
  [3., 4., 5.],
 ]
 jshell> array.argMax(0);
 ND: (3) cpu() int64
 [1, 1, 1]
 jshell> array.argMax(1);
 ND: (2) cpu() int64
 [2, 2]
      Specified by:
      argMax in interface NDArray
      Parameters:
      axis - the axis along which to find maximum values
      Returns:
      a NDArray containing indices

    • topK

      public NDList topK(int k, int axis, boolean largest, boolean sorted)
      Returns (values, indices) of the top k values along given axis.
      Specified by:
      topK in interface NDArray
      Parameters:
      k - the number of returned values
      axis - the axis to sort along, whose shape is reduced to k
      largest - whether the largest or the smallest
      sorted - whether the sorted or not
      Returns:
      a NDList containing (values, indices)

    • argMin

      public NDArray argMin()
      Returns the indices of the minimum values into the flattened NDArray.

      Examples 

       jshell> NDArray array = manager.arange(6f).reshape(2, 3);
 jshell> array;
 ND: (2, 3) cpu() float32
 [[0., 1., 2.],
  [3., 4., 5.],
 ]
 jshell> array.argMin();
 ND: () cpu() int64
 0.
      Specified by:
      argMin in interface NDArray
      Returns:
      a NDArray containing indices

    • argMin

      public NDArray argMin(int axis)
      Returns the indices of the minimum values along given axis.

      Examples 

       jshell> NDArray array = manager.arange(6f).reshape(2, 3);
 jshell> array;
 ND: (2, 3) cpu() float32
 [[0., 1., 2.],
  [3., 4., 5.],
 ]
 jshell> array.argMin(0);
 ND: (3) cpu() int64
 [0, 0, 0]
 jshell> array.argMin(1);
 ND: (2) cpu() int64
 [0, 0]
      Specified by:
      argMin in interface NDArray
      Parameters:
      axis - the axis along which to find minimum values
      Returns:
      a NDArray containing indices

    • percentile

      public NDArray percentile(Number percentile)
      Returns percentile for this NDArray.
      Specified by:
      percentile in interface NDArray
      Parameters:
      percentile - the target percentile in range of 0..100
      Returns:
      the result NDArray

    • percentile

      public NDArray percentile(Number percentile, int[] axes)
      Returns median along given dimension(s).
      Specified by:
      percentile in interface NDArray
      Parameters:
      percentile - the target percentile in range of 0..100
      axes - the dimension to calculate percentile for
      Returns:
      the result NDArray NDArray

    • median

      public NDArray median()
      Returns median value for this NDArray.
      Specified by:
      median in interface NDArray
      Returns:
      the median NDArray

    • median

      public NDArray median(int[] axes)
      Returns median value along given axes.
      Specified by:
      median in interface NDArray
      Parameters:
      axes - the axes along which to perform the median operation
      Returns:
      the median NDArray along the specified axes

    • toDense

      public NDArray toDense()
      Returns a dense representation of the sparse NDArray.
      Specified by:
      toDense in interface NDArray
      Returns:
      the result NDArray

    • toSparse

      public NDArray toSparse(SparseFormat fmt)
      Returns a sparse representation of NDArray.
      Specified by:
      toSparse in interface NDArray
      Parameters:
      fmt - the SparseFormat of this NDArray
      Returns:
      the result NDArray

    • nonzero

      public NDArray nonzero()
      Returns the indices of elements that are non-zero.

      Note that the behavior is slightly different from numpy.nonzero. Numpy returns a tuple of NDArray, one for each dimension of NDArray. DJL nonzero returns only one NDArray with last dimension containing all dimension of indices.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 1f, 1f, 0f, 1f});
 jshell> array.nonzero();
 ND: (4, 1) cpu() int64
 [[ 0],
  [ 1],
  [ 2],
  [ 4],
 ]
 jshell> array = manager.create(new float[] {3f, 0f, 0f, 0f, 4f, 0f, 5f, 6f, 0f}).reshape(3, 3);
 jshell> array;
 ND: (3, 3) cpu() float32
 [[3., 0., 0.],
  [0., 4., 0.],
  [5., 6., 0.],
 ]
 jshell> array.nonzero();
 ND: (4, 2) cpu() int64
 [[ 0,  0],
  [ 1,  1],
  [ 2,  0],
  [ 2,  1],
 ]
      Specified by:
      nonzero in interface NDArray
      Returns:
      the indices of the elements that are non-zero

    • erfinv

      public NDArray erfinv()
      Returns element-wise inverse gauss error function of the NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 0.5f, -1f});
 jshell> array.erfinv();
 ND: (3) cpu() float32
 [0., 0.4769, -inf]
      Specified by:
      erfinv in interface NDArray
      Returns:
      The inverse of gauss error of the NDArray, element-wise

    • erf

      public NDArray erf()
      Returns element-wise gauss error function of the NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {0f, 0.4769f, Float.NEGATIVE_INFINITY});
 jshell> array.erf();
 ND: (3) cpu() float32
 [0., 0.5, -1]
      Specified by:
      erf in interface NDArray
      Returns:
      The gauss error of the NDArray, element-wise

    • inverse

      public NDArray inverse()
      Computes the inverse of square NDArray if it exists.
      Specified by:
      inverse in interface NDArray
      Returns:
      the inverse of square NDArray.

    • norm

      public NDArray norm(boolean keepDims)
      Returns the norm of this NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {-3f, -4f});
 jshell> array.norm(true);
 ND: () cpu() float32
 5.
 jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array.norm(true);
 ND: () cpu() float32
 [[5.4772],
 ]
      Specified by:
      norm in interface NDArray
      Parameters:
      keepDims - If this is set to True, the axes which are normed over are left in the result as dimensions with size one. With this option the result will broadcast correctly against the original x.
      Returns:
      the norm of this NDArray

    • norm

      public NDArray norm(int ord, int[] axes, boolean keepDims)
      Returns the norm of this NDArray.

      Examples 

       jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array.norm(2, new int[] {0}, true);
 ND: (1, 2) cpu() float32
 [[3.1623, 4.4721],
 ]
 jshell> NDArray array = manager.create(new float[] {1f, 2f, 3f, 4f}, new Shape(2, 2));
 jshell> array.norm(2, new int[] {0}, false);
 ND: (2) cpu() float32
 [3.1623, 4.4721]
      Specified by:
      norm in interface NDArray
      Parameters:
      ord - Order of the norm.
      axes - If axes contains an integer, it specifies the axis of x along which to compute the vector norms. If axis contains 2 integers, it specifies the axes that hold 2-D matrices, and the matrix norms of these matrices are computed.
      keepDims - keepDims If this is set to True, the axes which are normed over are left in the result as dimensions with size one. With this option the result will broadcast correctly against the original x.
      Returns:
      the norm of this NDArray

    • oneHot

      public NDArray oneHot(int depth, float onValue, float offValue, DataType dataType)
      Returns a one-hot NDArray.
      • The locations represented by indices take value onValue, while all other locations take value offValue.
      • If the input NDArray is rank N, the output will have rank N+1. The new axis is appended at the end.
      • If NDArray is a scalar the output shape will be a vector of length depth.
      • If NDArray is a vector of length features, the output shape will be features x depth.
      • If NDArray is a matrix with shape [batch, features], the output shape will be batch x features x depth.

      Examples 

       jshell> NDArray array = manager.create(new int[] {1, 0, 2, 0});
 jshell> array.oneHot(3, 8f, 1f, array.getDataType());
 ND: (4, 3) cpu() int32
 [[ 1,  8,  1],
  [ 8,  1,  1],
  [ 1,  1,  8],
  [ 8,  1,  1],
 ]
      Specified by:
      oneHot in interface NDArray
      Parameters:
      depth - Depth of the one hot dimension.
      onValue - The value assigned to the locations represented by indices.
      offValue - The value assigned to the locations not represented by indices.
      dataType - dataType of the output.
      Returns:
      one-hot encoding of this NDArray
      See Also:

    • batchDot

      public NDArray batchDot(NDArray other)
      Batchwise product of this NDArray and the other NDArray.
      • batchDot is used to compute dot product of x and y when x and y are data in batch, namely N-D (N greater or equal to 3) arrays in shape of (B0, …, B_i, :, :). For example, given x with shape (B_0, …, B_i, N, M) and y with shape (B_0, …, B_i, M, K), the result array will have shape (B_0, …, B_i, N, K), which is computed by: batch_dot(x,y)[b_0, ..., b_i, :, :] = dot(x[b_0, ..., b_i, :, :], y[b_0, ..., b_i, :, :])

      Examples 

       jshell> NDArray array1 = manager.ones(new Shape(2, 1, 4));
 jshell> NDArray array2 = manager.ones(new Shape(2, 4, 6));
 jshell> array1.batchDot(array2);
 ND: (2, 1, 6) cpu() float32
 [[[4., 4., 4., 4., 4., 4.],
  ],
  [[4., 4., 4., 4., 4., 4.],
  ],
 ]
      Specified by:
      batchDot in interface NDArray
      Parameters:
      other - the other NDArray to perform batch dot product with
      Returns:
      the result NDArray

    • complex

      public NDArray complex()
      Convert a general NDArray to its complex math format.

      example: [10f, 12f] float32 -> [10+12j] in complex64

      Specified by:
      complex in interface NDArray
      Returns:
      the complex NDArray

    • real

      public NDArray real()
      Convert a complex NDArray to its real math format. example: [10+12j] in complex64 -> [10f, 12f] float32
      Specified by:
      real in interface NDArray
      Returns:
      tje real NDArray

    • conj

      public NDArray conj()
      Conjugate complex array.
      Specified by:
      conj in interface NDArray
      Returns:
      Returns a view of input with a flipped conjugate bit. If input has a non-complex type, this function just returns input.

    • getNDArrayInternal

      public ai.djl.ndarray.internal.NDArrayEx getNDArrayInternal()
      Returns an internal representative of Native NDArray.

      This method should only be used by Engine provider

      Specified by:
      getNDArrayInternal in interface NDArray
      Returns:
      an internal representative of Native NDArray

    • isReleased

      public boolean isReleased()
      Returns true if this NDArray has been released.
      Specified by:
      isReleased in interface NDArray
      Returns:
      true if this NDArray has been released

    • close

      public void close()
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface NDArray
      Specified by:
      close in interface NDResource

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • toString

      public String toString()
      Overrides:
      toString in class Object