org.nd4j.linalg.api.blas

Class BlasBufferUtil

java.lang.Object

org.nd4j.linalg.api.blas.BlasBufferUtil

public class BlasBufferUtil
extends Object

Blas buffer util for interopping with the underlying buffers and the given ndarrays

Author:

Adam Gibson

Constructor Summary

Constructors

Constructor and Description
BlasBufferUtil()

Method Summary

Modifier and Type	Method and Description
static int	getBlasOffset(INDArray arr) Get blas stride for the given array
static int	getBlasStride(INDArray arr) Get blas stride for the given array
static char	getCharForTranspose(INDArray arr) Returns the proper character for how to interpret a buffer (fortran being N C being T)
static int	getDimension(INDArray arr, boolean defaultRows) Get the dimension associated with the given ordering.
static double[]	getDoubleData(DataBuffer buf) Returns the double data for this buffer.
static double[]	getDoubleData(INDArray buf) Returns the double data for this ndarray.
static float[]	getFloatData(DataBuffer buf) Returns the float data for this buffer.
static float[]	getFloatData(INDArray buf) Returns the float data for this ndarray.
static int	getLd(INDArray arr) Get the leading dimension for a blas invocation.
static int	getStrideForOrdering(INDArray arr) Return the proper stride through a vector relative to the ordering of the array This is for incX/incY parameters in BLAS.
static void	setData(double[] data, INDArray toSet) Set the data for the underlying array.
static void	setData(float[] data, INDArray toSet) Set the data for the underlying array.

Methods inherited from class java.lang.Object

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

Constructor Detail

BlasBufferUtil

public BlasBufferUtil()

Method Detail

getBlasOffset

public static int getBlasOffset(INDArray arr)

Get blas stride for the given array

Parameters:

arr - the array

Returns:

the blas stride

getBlasStride

public static int getBlasStride(INDArray arr)

Get blas stride for the given array

Parameters:

arr - the array

Returns:

the blas stride

getFloatData

public static float[] getFloatData(INDArray buf)

Returns the float data for this ndarray. If possible (the offset is 0 representing the whole buffer) it will return a direct reference to the underlying array

Parameters:

buf - the ndarray to get the data for

Returns:

the float data for this ndarray

getDoubleData

public static double[] getDoubleData(INDArray buf)

Returns the double data for this ndarray. If possible (the offset is 0 representing the whole buffer) it will return a direct reference to the underlying array

Parameters:

buf - the ndarray to get the data for

Returns:

the double data for this ndarray

getCharForTranspose

public static char getCharForTranspose(INDArray arr)

Returns the proper character for how to interpret a buffer (fortran being N C being T)

Parameters:

arr - the array to get the transpose for

Returns:

the character for transpose of a particular array

getStrideForOrdering

public static int getStrideForOrdering(INDArray arr)

Return the proper stride through a vector relative to the ordering of the array This is for incX/incY parameters in BLAS.

Parameters:

arr - the array to get the stride for

Returns:

the stride wrt the ordering for the given array

getDimension

public static int getDimension(INDArray arr,
                               boolean defaultRows)

Get the dimension associated with the given ordering. When working with blas routines, they typically assume c ordering, instead you can invert the rows/columns which enable you to do no copy blas operations.

Parameters:

arr -

defaultRows -

Returns:

getLd

public static int getLd(INDArray arr)

Get the leading dimension for a blas invocation. The lead dimension is usually arr.size(0) (this is only for fortran ordering though). It can be size(1) (assuming matrix) for C ordering though.

Parameters:

arr - the array to

Returns:

the leading dimension wrt the ordering of the array

getFloatData

public static float[] getFloatData(DataBuffer buf)

Returns the float data for this buffer. If possible (the offset is 0 representing the whole buffer) it will return a direct reference to the underlying array

Parameters:

buf - the ndarray to get the data for

Returns:

the double data for this ndarray

getDoubleData

public static double[] getDoubleData(DataBuffer buf)

Returns the double data for this buffer. If possible (the offset is 0 representing the whole buffer) it will return a direct reference to the underlying array

Parameters:

buf - the ndarray to get the data for

Returns:

the double data for this buffer

setData

public static void setData(float[] data,
                           INDArray toSet)

Set the data for the underlying array. If the underlying buffer's array is equivalent to this array it returns (avoiding an unneccessary copy) If the underlying storage mechanism isn't heap (no arrays) it just copied the data over (strided access with offsets where neccessary) This is meant to be used with blas operations where the underlying blas implementation takes an array but the data buffer being used might not be an array. This is also for situations where there is strided access and it's not optimal to want to use the whole data buffer but just the subset of the buffer needed for calculations.

Parameters:

data - the data to set

toSet - the array to set the data to

setData

public static void setData(double[] data,
                           INDArray toSet)

Set the data for the underlying array. If the underlying buffer's array is equivalent to this array it returns (avoiding an unneccessary copy) If the underlying storage mechanism isn't heap (no arrays) it just copied the data over (strided access with offsets where neccessary) This is meant to be used with blas operations where the underlying blas implementation takes an array but the data buffer being used might not be an array. This is also for situations where there is strided access and it's not optimal to want to use the whole data buffer but just the subset of the buffer needed for calculations.

Parameters:

data - the data to set

toSet - the array to set the data to