Module org.tensorflow.ndarray

Package org.tensorflow.ndarray.index

Class Indices

java.lang.Object

org.tensorflow.ndarray.index.Indices

public final class Indices
extends Object

Helper class for instantiating Index objects.

Constructor Summary

Constructors

Constructor	Description
Indices()

Method Summary

Modifier and Type	Method	Description
static Index	all()	An index that returns all elements of a dimension in the original order.
static Index	at(long coord)	A coordinate that selects a specific element on a given dimension.
static Index	at(long coord, boolean keepDim)	A coordinate that selects a specific element on a given dimension.
static Index	at(NdArray<? extends Number> coord)	A coordinate that selects a specific element on a given dimension.
static Index	at(NdArray<? extends Number> coord, boolean keepDim)	A coordinate that selects a specific element on a given dimension.
static Index	ellipsis()	An index that expands to fill all available source dimensions.
static Index	even()	An index that returns only elements found at an even position in the original dimension.
static Index	flip()	An index that returns only elements on a given dimension between two coordinates.
static Index	hyperslab(long start, long stride, long count, long block)	An index that returns elements according to an hyperslab defined by start, stride, count, block.
static Index	newAxis()	An index that inserts a new dimension of size 1 into the resulting array.
static Index	odd()	An index that returns only elements found at an odd position in the original dimension.
static Index	range(long start, long end)	An index that returns only elements on a given dimension between two coordinates.
static Index	seq(long... coords)	An index that returns only specific elements on a given dimension.
static Index	seq(NdArray<? extends Number> coords)	An index that returns only specific elements on a given dimension.
static Index	slice(long start, long end)	An index that returns elements between start and end.
static Index	slice(long start, long end, long stride)	An index that returns every stride-th element between start and end.
static Index	slice(Long start, Long end)	An index that returns elements between start and end.
static Index	slice(Long start, Long end, long stride)	An index that returns every stride-th element between start and end.
static Index	sliceFrom(long start)	An index that returns only elements on a given dimension starting at a specific coordinate.
static Index	sliceFrom(long start, long stride)	An index that returns only elements on a given dimension starting at a specific coordinate, using the given stride.
static Index	sliceTo(long end)	An index that returns only elements on a given dimension up to a specific coordinate.
static Index	sliceTo(long end, long stride)	An index that returns only elements on a given dimension up to a specific coordinate, using the given stride.
static Index	step(long stride)	An index that skips a fixed amount of coordinates between each values returned.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Indices

public Indices()

Method Detail

at

public static Index at(long coord)

A coordinate that selects a specific element on a given dimension.

When this index is applied to a given dimension, the dimension is resolved as a single element and therefore is excluded from the computation of the rank.

For example, given a 3D matrix on the axis [x, y, z], if matrix.slice(all(), at(0), at(0), then the rank of the returned slice is 1 and its number of elements is x.numElements()

Parameters:

coord - coordinate of the element on the indexed axis

Returns:

index

at

public static Index at(NdArray<? extends Number> coord)

A coordinate that selects a specific element on a given dimension.

This is equivalent to call at(long) but where the value of the coordinate is provided by an N-dimensional array.

Parameters:

coord - scalar indicating the coordinate of the element on the indexed axis

Returns:

index

Throws:

IllegalRankException - if coord is not a scalar (rank 0)

at

public static Index at(long coord,
                       boolean keepDim)

A coordinate that selects a specific element on a given dimension.

When this index is applied to a given dimension, the dimension is resolved as a single element and therefore, if keepDim is false, is excluded from the computation of the rank. If keepDim is true, the dimension is collapsed down to one element.

For example, given a 3D matrix on the axis [x, y, z], if matrix.slice(all(), at(0), at(0), then the rank of the returned slice is 1 and its number of elements is x.numElements()

Parameters:

coord - coordinate of the element on the indexed axis

keepDim - whether to remove the dimension.

Returns:

index

at

public static Index at(NdArray<? extends Number> coord,
                       boolean keepDim)

A coordinate that selects a specific element on a given dimension.

This is equivalent to call at(long, boolean) but where the value of the coordinate is provided by an N-dimensional array.

If keepDim is true, the dimension is collapsed down to one element instead of being removed.

Parameters:

coord - scalar indicating the coordinate of the element on the indexed axis

keepDim - whether to remove the dimension.

Returns:

index

Throws:

IllegalRankException - if coord is not a scalar (rank 0)

all

public static Index all()

An index that returns all elements of a dimension in the original order.

Applying this index to a given dimension will return the original dimension directly.

For example, given a vector with n elements, all() returns x₀, x₁, ..., x_n-1

Returns:

index

seq

public static Index seq(long... coords)

An index that returns only specific elements on a given dimension.

For example, given a vector with n elements on the x axis, and n > 10, seq(8, 0, 3) returns x₈, x₀, x₃

Parameters:

coords - coordinates of the elements in the sequence

Returns:

index

seq

public static Index seq(NdArray<? extends Number> coords)

An index that returns only specific elements on a given dimension.

This is equivalent to seq(long...) but where the coordinates of the elements in the sequence are provided by an N-dimensional array.

Parameters:

coords - vector of coordinates of the elements in the sequence

Returns:

index

Throws:

IllegalRankException - if coords is not a vector (rank 1)

even

public static Index even()

An index that returns only elements found at an even position in the original dimension.

For example, given a vector with n elements on the x axis, and n is even, even() returns x₀, x₂, ..., x_n-2

Returns:

index

odd

public static Index odd()

An index that returns only elements found at an odd position in the original dimension.

For example, given a vector with n elements on the x axis, and n is even, odd() returns x₁, x₃, ..., x_n-1

Returns:

index

step

public static Index step(long stride)

An index that skips a fixed amount of coordinates between each values returned.

For example, given a vector with n elements on the x axis, step(k) returns x₀, x_k, x_k*2, ...

Parameters:

stride - the number of elements between each steps

Returns:

index

sliceFrom

public static Index sliceFrom(long start)

An index that returns only elements on a given dimension starting at a specific coordinate.

For example, given a vector with n elements on the x axis, and n > k, from(k) returns x_k, x_k+1, ..., x_n-1

Parameters:

start - coordinate of the first element of the sequence

Returns:

index

sliceFrom

public static Index sliceFrom(long start,
                              long stride)

An index that returns only elements on a given dimension starting at a specific coordinate, using the given stride.

For example, given a vector with n elements on the x axis, and n > k, from(k) returns x_k, x_k+1, ..., x_n-1

Parameters:

start - coordinate of the first element of the sequence

stride - the stride to use

Returns:

index

See Also:

slice(long, long, long)

sliceTo

public static Index sliceTo(long end)

An index that returns only elements on a given dimension up to a specific coordinate.

For example, given a vector with n elements on the x axis, and n > k, to(k) returns x₀, x₁, ..., x_k

Parameters:

end - coordinate of the last element of the sequence (exclusive)

Returns:

index

sliceTo

public static Index sliceTo(long end,
                            long stride)

An index that returns only elements on a given dimension up to a specific coordinate, using the given stride.

For example, given a vector with n elements on the x axis, and n > k, to(k) returns x₀, x₁, ..., x_k

Parameters:

end - coordinate of the last element of the sequence (exclusive)

stride - the stride to use

Returns:

index

See Also:

slice(long, long, long)

range

public static Index range(long start,
                          long end)

An index that returns only elements on a given dimension between two coordinates.

For example, given a vector with n elements on the x axis, and n > k > j, range(j, k) returns x_j, x_j+1, ..., x_k

Parameters:

start - coordinate of the first element of the sequence

end - coordinate of the last element of the sequence (exclusive)

Returns:

index

flip

public static Index flip()

An index that returns only elements on a given dimension between two coordinates.

For example, given a vector with n elements on the x axis, and n > k > j, range(j, k) returns x_j, x_j+1, ..., x_k

Returns:

index

hyperslab

public static Index hyperslab(long start,
                              long stride,
                              long count,
                              long block)

An index that returns elements according to an hyperslab defined by start, stride, count, block. See Hyperslab.

Parameters:

start - Starting location for the hyperslab.

stride - The number of elements to separate each element or block to be selected.

count - The number of elements or blocks to select along the dimension.

block - The size of the block selected from the dimension.

Returns:

index

newAxis

public static Index newAxis()

An index that inserts a new dimension of size 1 into the resulting array.

Returns:

index

ellipsis

public static Index ellipsis()

An index that expands to fill all available source dimensions. Works the same as Python's ....

Returns:

index

slice

public static Index slice(long start,
                          long end)

An index that returns elements between start and end. If start or end is null, starts or ends at the beginning or the end, respectively.

Analogous to Python's : slice syntax.

Returns:

index

slice

public static Index slice(long start,
                          long end,
                          long stride)

An index that returns every stride-th element between start and end. If start or end is null, starts or ends at the beginning or the end, respectively.

Analogous to Python's : slice syntax.

Returns:

index

slice

public static Index slice(Long start,
                          Long end)

An index that returns elements between start and end. If start or end is null, starts or ends at the beginning or the end, respectively.

Analogous to Python's : slice syntax.

Returns:

index

slice

public static Index slice(Long start,
                          Long end,
                          long stride)

An index that returns every stride-th element between start and end. If start or end is null, starts or ends at the beginning or the end, respectively.

Analogous to Python's : slice syntax.

Returns:

index