Class ByteSparseNdArray

java.lang.Object
org.tensorflow.ndarray.impl.sparse.AbstractSparseNdArray<Byte, ByteNdArray>
org.tensorflow.ndarray.impl.sparse.ByteSparseNdArray
All Implemented Interfaces:
ByteNdArray, NdArray<Byte>, Shaped, SparseNdArray<Byte, ByteNdArray>
public class ByteSparseNdArray extends AbstractSparseNdArray<Byte, ByteNdArray> implements ByteNdArray
sparse array for the byte data type

A sparse array as two separate dense arrays: indices, values, and a shape that represents the dense shape.

NOTE: all Sparse Arrays are readonly for the set(NdArray, long...) and setObject(Byte, long...) methods 

ByteSparseNdArray st = new ByteSparseNdArray(
     StdArrays.of(new long[][] {{0, 0}, {1, 2}}),
     NdArrays.vectorOf((byte)1, (byte)255),
     Shape.of(3, 4));

represents the dense array: 

[[(byte)1, (byte)0, (byte)0, (byte)0]
 [(byte)0, (byte)0, (byte)1, (byte)0]
 [(byte)0, (byte)0, (byte)0, (byte)0]]

  • Field Details

  • Constructor Details

    • ByteSparseNdArray

      protected ByteSparseNdArray(LongNdArray indices, ByteNdArray values, byte defaultValue, DimensionalSpace dimensions)
      Creates a ByteSparseNdArray with a default value of zero.
      Parameters:
      indices - A 2-D LongNdArray of shape [N, ndims], that specifies the indices of the elements in the sparse array that contain non-default values (elements are zero-indexed). For example, indices=[[1,3], [2,4]] specifies that the elements with indexes of [1,3] and [2,4] have non-default values.
      values - A 1-D NdArray of Byte type and shape [N], which supplies the values for each element in indices. For example, given indices=[[1,3], [2,4]], the parameter values=[18, 3.6] specifies that element [1,3] of the sparse NdArray has a value of 18, and element [2,4] of the NdArray has a value of 3.6.
      defaultValue - Scalar value to set for indices not specified in AbstractSparseNdArray.getIndices()
      dimensions - the dimensional space for the dense object represented by this sparse array,

  • Method Details

    • create

      public static ByteSparseNdArray create(LongNdArray indices, ByteNdArray values, DimensionalSpace dimensions)
      Creates a new ByteSparseNdArray
      Parameters:
      indices - A 2-D LongNdArray of shape [N, ndims], that specifies the indices of the elements in the sparse array that contain non-default values (elements are zero-indexed). For example, indices=[[1,3], [2,4]] specifies that the elements with indexes of [1,3] and [2,4] have non-default values.
      values - A 1-D NdArray of any type and shape [N], which supplies the values for each element in indices. For example, given indices=[[1,3], [2,4]], the parameter values=[18, 3.6] specifies that element [1,3] of the sparse NdArray has a value of 18, and element [2,4] of the NdArray has a value of 3.6.
      dimensions - the dimensional space for the dense object represented by this sparse array.
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(LongNdArray indices, ByteNdArray values, byte defaultValue, DimensionalSpace dimensions)
      Creates a new ByteSparseNdArray
      Parameters:
      indices - A 2-D LongNdArray of shape [N, ndims], that specifies the indices of the elements in the sparse array that contain non-default values (elements are zero-indexed). For example, indices=[[1,3], [2,4]] specifies that the elements with indexes of [1,3] and [2,4] have non-default values.
      values - A 1-D NdArray of any type and shape [N], which supplies the values for each element in indices. For example, given indices=[[1,3], [2,4]], the parameter values=[18, 3.6] specifies that element [1,3] of the sparse NdArray has a value of 18, and element [2,4] of the NdArray has a value of 3.6.
      defaultValue - Scalar value to set for indices not specified in AbstractSparseNdArray.getIndices()
      dimensions - the dimensional space for the dense object represented by this sparse array.
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(ByteDataBuffer dataBuffer, DimensionalSpace dimensions)
      Creates a new ByteSparseNdArray from a data buffer
      Parameters:
      dataBuffer - the databuffer containing the dense array
      dimensions - the dimensional space for the sparse array
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(ByteDataBuffer dataBuffer, byte defaultValue, DimensionalSpace dimensions)
      Creates a new ByteSparseNdArray from a data buffer
      Parameters:
      dataBuffer - the databuffer containing the dense array
      defaultValue - Scalar value to set for indices not specified in AbstractSparseNdArray.getIndices()
      dimensions - the dimensional space for the sparse array
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(DimensionalSpace dimensions)
      Creates a new empty ByteSparseNdArray from a data buffer
      Parameters:
      dimensions - the dimensions array
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(byte defaultValue, DimensionalSpace dimensions)
      Creates a new empty ByteSparseNdArray from a data buffer
      Parameters:
      defaultValue - Scalar value to set for indices not specified in AbstractSparseNdArray.getIndices()
      dimensions - the dimensions array
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(ByteDataBuffer buffer, Shape shape)
      Creates a new empty ByteSparseNdArray from a float data buffer
      Parameters:
      buffer - the data buffer
      shape - the shape of the sparse array.
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(ByteDataBuffer buffer, byte defaultValue, Shape shape)
      Creates a new empty ByteSparseNdArray from a float data buffer
      Parameters:
      buffer - the data buffer
      defaultValue - Scalar value to set for indices not specified in AbstractSparseNdArray.getIndices()
      shape - the shape of the sparse array.
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(ByteNdArray src)
      Creates a new ByteSparseNdArray from a ByteNdArray
      Parameters:
      src - the ByteNdArray
      Returns:
      the new Sparse Array

    • create

      public static ByteSparseNdArray create(ByteNdArray src, byte defaultValue)
      Creates a new ByteSparseNdArray from a ByteNdArray
      Parameters:
      src - the ByteNdArray
      defaultValue - Scalar value to set for indices not specified in AbstractSparseNdArray.getIndices()
      Returns:
      the new Sparse Array

    • createValues

      public ByteNdArray createValues(Shape shape)
      Creates a ByteNdArray of the specified shape
      Specified by:
      createValues in class AbstractSparseNdArray<Byte, ByteNdArray>
      Parameters:
      shape - the shape of the dense array.
      Returns:
      a ByteNdArray of the specified shape

    • slice

      public ByteNdArray slice(long position, DimensionalSpace sliceDimensions)

    • getByte

      public byte getByte(long... coordinates)
      Returns the byte value of the scalar found at the given coordinates.

      To access the scalar element, the number of coordinates provided must be equal to the number of dimensions of this array (i.e. its rank). For example: 

       ByteNdArray matrix = NdArrays.ofBytes(shape(2, 2));  // matrix rank = 2
 matrix.getByte(0, 1);  // succeeds, returns 0
 matrix.getByte(0);  // throws IllegalRankException

 ByteNdArray scalar = matrix.get(0, 1);  // scalar rank = 0
 scalar.getByte();  // succeeds, returns 0
      Specified by:
      getByte in interface ByteNdArray
      Parameters:
      coordinates - coordinates of the scalar to resolve
      Returns:
      value of that scalar

    • setByte

      public ByteNdArray setByte(byte value, long... coordinates)
      Assigns the byte value of the scalar found at the given coordinates.

      To access the scalar element, the number of coordinates provided must be equal to the number of dimensions of this array (i.e. its rank). For example: 

       ByteNdArray matrix = NdArrays.ofBytes(shape(2, 2));  // matrix rank = 2
 matrix.setByte(10, 0, 1);  // succeeds
 matrix.setByte(10, 0);  // throws IllegalRankException

 ByteNdArray scalar = matrix.get(0, 1);  // scalar rank = 0
 scalar.setByte(10);  // succeeds
      Specified by:
      setByte in interface ByteNdArray
      Parameters:
      value - the value to assign
      coordinates - coordinates of the scalar to assign
      Returns:
      this array

    • copyTo

      public ByteNdArray copyTo(DataBuffer<Byte> dst)
      Copy the content of this N-dimensional array into the destination buffer.

      The size of the buffer must be equal or greater to the Shaped.size() of this array, or an exception is thrown. After the copy, content of the buffer and of the array can be altered independently, without affecting each other.

      Note: in version 0.4.0 and earlier, this method was named read(DataBuffer<T>). It has been renamed to explicitly indicate the direction of the data flow to avoid confusion.

      Specified by:
      copyTo in interface ByteNdArray
      Specified by:
      copyTo in interface NdArray<Byte>
      Parameters:
      dst - the destination buffer
      Returns:
      this array
      See Also:

    • copyTo

      public ByteNdArray copyTo(ByteDataBuffer dst)
      Specified by:
      copyTo in interface ByteNdArray

    • copyFrom

      public ByteNdArray copyFrom(ByteDataBuffer src)
      Specified by:
      copyFrom in interface ByteNdArray

    • copyFrom

      public ByteNdArray copyFrom(DataBuffer<Byte> src)
      Copy the content of the source buffer into this N-dimensional array.

      The size of the buffer must be equal or greater to the Shaped.size() of this array, or an exception is thrown. After the copy, content of the buffer and of the array can be altered independently, without affecting each other.

      Note: in version 0.4.0 and earlier, this method was named write(DataBuffer<T>). It has been renamed to explicitly indicate the direction of the data flow to avoid confusion.

      Specified by:
      copyFrom in interface ByteNdArray
      Specified by:
      copyFrom in interface NdArray<Byte>
      Parameters:
      src - the source buffer
      Returns:
      this array
      See Also:

    • toDense

      public ByteNdArray toDense()
      Converts the sparse array to a dense array
      Specified by:
      toDense in class AbstractSparseNdArray<Byte, ByteNdArray>
      Returns:
      the dense array

    • fromDense

      public ByteNdArray fromDense(ByteNdArray src)
      Populates this sparse array from a dense array
      Parameters:
      src - the dense array
      Returns:
      this sparse array

    • slice

      public ByteNdArray slice(Index... indices)
      Creates a multi-dimensional view (or slice) of this array by mapping one or more dimensions to the given index selectors.

      Slices allow to traverse an N-dimensional array in any of its axis and/or to filter only elements of interest. For example, for a given matrix on the [x, y] axes, it is possible to iterate elements at y=0 for all x.

      Any changes applied to the returned slice affect the data of this array as well, as there is no copy involved.

      Example of usage: 

         FloatNdArray matrix3d = NdArrays.ofFloats(shape(3, 2, 4));  // with [x, y, z] axes

   // Iterates elements on the x axis by preserving only the 3rd value on the z axis,
   // (i.e. [x, y, 2])
   matrix3d.slice(all(), all(), at(2)).elements(0).forEach(m -> {
     assertEquals(shape(2), m); // y=2, z=0 (scalar)
   });

   // Creates a slice that contains only the last element of the y axis and elements with an
   // odd `z` coordinate.
   FloatNdArray slice = matrix3d.slice(all(), at(1), odd());
   assertEquals(shape(3, 2), slice.shape());  // x=3, y=0 (scalar), z=2 (odd coordinates)

   // Iterates backward the elements on the x axis
   matrix3d.slice(flip()).elements(0).forEach(m -> {
     assertEquals(shape(2, 4), m);  // y=2, z=4
   });
      Specified by:
      slice in interface ByteNdArray
      Specified by:
      slice in interface NdArray<Byte>
      Overrides:
      slice in class AbstractSparseNdArray<Byte, ByteNdArray>
      Parameters:
      indices - index selectors per dimensions, starting from dimension 0 of this array.
      Returns:
      the element resulting of the index selection

    • get

      public ByteNdArray get(long... coordinates)
      Returns the N-dimensional element of this array at the given coordinates.

      Elements of any of the dimensions of this array can be retrieved. For example, if the number of coordinates is equal to the number of dimensions of this array, then a rank-0 (scalar) array is returned, which value can then be obtained by calling `array.getObject()`.

      Any changes applied to the returned elements affect the data of this array as well, as there is no copy involved.

      Note that invoking this method is an equivalent and more efficient way to slice this array on single scalar, i.e. array.get(x, y, z) is equal to array.slice(at(x), at(y), at(z))

      Specified by:
      get in interface ByteNdArray
      Specified by:
      get in interface NdArray<Byte>
      Overrides:
      get in class AbstractSparseNdArray<Byte, ByteNdArray>
      Parameters:
      coordinates - coordinates of the element to access, none will return this array
      Returns:
      the element at this index

    • setObject

      public ByteNdArray setObject(Byte value, long... coordinates)
      Assigns the value of the scalar found at the given coordinates.

      To access the scalar element, the number of coordinates provided must be equal to the number of dimensions of this array (i.e. its rank). For example: 

       FloatNdArray matrix = NdArrays.ofFloats(shape(2, 2));  // matrix rank = 2
 matrix.setObject(10.0f, 0, 1);  // succeeds
 matrix.setObject(10.0f, 0);  // throws IllegalRankException

 FloatNdArray scalar = matrix.get(0, 1);  // scalar rank = 0
 scalar.setObject(10.0f);  // succeeds
      Note: if this array stores values of a primitive type, prefer the usage of the specialized method in the subclass for that type. For example, floatArray.setFloat(10.0f, 0);
      Specified by:
      setObject in interface ByteNdArray
      Specified by:
      setObject in interface NdArray<Byte>
      Overrides:
      setObject in class AbstractSparseNdArray<Byte, ByteNdArray>
      Parameters:
      value - the value to assign
      coordinates - coordinates of the scalar to assign
      Returns:
      this array

    • set

      public ByteNdArray set(NdArray<Byte> src, long... coordinates)
      Assigns the value of the N-dimensional element found at the given coordinates.

      The number of coordinates provided can be anywhere between 0 and rank - 1. For example: 

       FloatNdArray matrix = NdArrays.ofFloats(shape(2, 2));  // matrix rank = 2
 matrix.set(vector(10.0f, 20.0f), 0);  // success
 matrix.set(scalar(10.0f), 1, 0); // success
      Specified by:
      set in interface ByteNdArray
      Specified by:
      set in interface NdArray<Byte>
      Overrides:
      set in class AbstractSparseNdArray<Byte, ByteNdArray>
      Parameters:
      src - an array of the values to assign
      coordinates - coordinates of the element to assign
      Returns:
      this array

    • copyTo

      public ByteNdArray copyTo(NdArray<Byte> dst)
      Copy the content of this array to the destination array.

      The Shaped.shape() of the destination array must be equal to the shape of this array, or an exception is thrown. After the copy, the content of both arrays can be altered independently, without affecting each other.

      Specified by:
      copyTo in interface ByteNdArray
      Specified by:
      copyTo in interface NdArray<Byte>
      Overrides:
      copyTo in class AbstractSparseNdArray<Byte, ByteNdArray>
      Parameters:
      dst - array to receive a copy of the content of this array
      Returns:
      this array

    • createDefaultArray

      public ByteNdArray createDefaultArray()
      Creates the NdArray with the default value as a scalar
      Specified by:
      createDefaultArray in class AbstractSparseNdArray<Byte, ByteNdArray>
      Returns:
      the default NdArray of the default value as a scalar

    • dimensions

      public DimensionalSpace dimensions()

    • shape

      public Shape shape()
      Specified by:
      shape in interface Shaped
      Returns:
      the shape of this container

    • scalars

      public NdArraySequence<ByteNdArray> scalars()
      Description copied from interface: NdArray
      Returns a sequence of all scalars in this array.

      This is equivalent to call elements(shape().numDimensions() - 1)

      Specified by:
      scalars in interface NdArray<T>
      Returns:
      an NdArray sequence

    • slowHashCode

      protected int slowHashCode()

    • slowEquals

      protected boolean slowEquals(NdArray<?> array)