org.nd4j.linalg.util

Class NDArrayMath

java.lang.Object

org.nd4j.linalg.util.NDArrayMath

public class NDArrayMath
extends Object

Author:

Adam Gibson

Method Summary

Modifier and Type	Method and Description
static int	lengthPerSlice(INDArray arr) Return the length of a slice
static int	lengthPerSlice(INDArray arr, int... dimension) The number of elements in a slice along a set of dimensions
static int	mapIndexOntoTensor(int index, INDArray arr, int... rank) This maps an index of a vector on to a vector in the matrix that can be used for indexing in to a tensor
static int	mapIndexOntoVector(int index, INDArray arr) This maps an index of a vector on to a vector in the matrix that can be used for indexing in to a tensor
static int	matricesPerSlice(INDArray arr) The number of vectors in each slice of an ndarray.
static int	numVectors(INDArray arr) Return the number of vectors for an array the number of vectors for an array
static int	offsetForSlice(INDArray arr, int slice) Compute the offset for a given slice
static int	sliceOffsetForTensor(int index, INDArray arr, int[] tensorShape) calculates the offset for a tensor
static int	tensorsPerSlice(INDArray arr, int[] tensorShape) Computes the tensors per slice given a tensor shape and array
static int	vectorsPerSlice(INDArray arr) The number of vectors in each slice of an ndarray.
static int	vectorsPerSlice(INDArray arr, int... rank) The number of vectors in each slice of an ndarray.

Methods inherited from class java.lang.Object

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

Method Detail

offsetForSlice

public static int offsetForSlice(INDArray arr,
                                 int slice)

Compute the offset for a given slice

Parameters:

arr - the array to compute the offset frm

slice - the slice to compute the offset for

Returns:

the offset for a given slice

lengthPerSlice

public static int lengthPerSlice(INDArray arr,
                                 int... dimension)

The number of elements in a slice along a set of dimensions

Parameters:

arr - the array to calculate the length per slice for

dimension - the dimensions to do the calculations along

Returns:

the number of elements in a slice along arbitrary dimensions

lengthPerSlice

public static int lengthPerSlice(INDArray arr)

Return the length of a slice

Parameters:

arr - the array to get the length of a slice for

Returns:

the number of elements per slice in an array

numVectors

public static int numVectors(INDArray arr)

Return the number of vectors for an array the number of vectors for an array

Parameters:

arr - the array to calculate the number of vectors for

Returns:

the number of vectors for the given array

vectorsPerSlice

public static int vectorsPerSlice(INDArray arr)

The number of vectors in each slice of an ndarray.

Parameters:

arr - the array to get the number of vectors per slice for

Returns:

the number of vectors per slice

tensorsPerSlice

public static int tensorsPerSlice(INDArray arr,
                                  int[] tensorShape)

Computes the tensors per slice given a tensor shape and array

Parameters:

arr - the array to get the tensors per slice for

tensorShape - the desired tensor shape

Returns:

the tensors per slice of an ndarray

matricesPerSlice

public static int matricesPerSlice(INDArray arr)

The number of vectors in each slice of an ndarray.

Parameters:

arr - the array to get the number of vectors per slice for

Returns:

the number of vectors per slice

vectorsPerSlice

public static int vectorsPerSlice(INDArray arr,
                                  int... rank)

The number of vectors in each slice of an ndarray.

Parameters:

arr - the array to get the number of vectors per slice for

rank - the dimensions to get the number of vectors per slice for

Returns:

the number of vectors per slice

sliceOffsetForTensor

public static int sliceOffsetForTensor(int index,
                                       INDArray arr,
                                       int[] tensorShape)

calculates the offset for a tensor

Parameters:

index -

arr -

tensorShape -

Returns:

mapIndexOntoTensor

public static int mapIndexOntoTensor(int index,
                                     INDArray arr,
                                     int... rank)

This maps an index of a vector on to a vector in the matrix that can be used for indexing in to a tensor

Parameters:

index - the index to map

arr - the array to use for indexing

rank - the dimensions to compute a slice for

Returns:

the mapped index

mapIndexOntoVector

public static int mapIndexOntoVector(int index,
                                     INDArray arr)

This maps an index of a vector on to a vector in the matrix that can be used for indexing in to a tensor

Parameters:

index - the index to map

arr - the array to use for indexing

Returns:

the mapped index