org.apfloat.internal

Class Long3NTTConvolutionStrategy

java.lang.Object

org.apfloat.internal.LongElementaryModMath

org.apfloat.internal.LongModMath

org.apfloat.internal.Long3NTTConvolutionStrategy

All Implemented Interfaces:

ConvolutionStrategy

public class Long3NTTConvolutionStrategy
extends LongModMath
implements ConvolutionStrategy

Convolution methods in the transform domain for the long type. Multiplication can be done in linear time in the transform domain, where the multiplication is simply an element-by-element multiplication.

This implementation uses three Number Theoretic Transforms to do the convolution and the Chinese Remainder Theorem to get the final result.

After transforming the data, the in-place multiplication (or squaring) of the data elements is done using a parallel algorithm, if the data fits in memory.

All access to this class must be externally synchronized.

Version:

1.6.1

Author:

Mikko Tommila

Constructor Summary

Constructors

Constructor and Description
Long3NTTConvolutionStrategy(int radix, NTTStrategy transform) Creates a new convoluter that uses the specified transform for transforming the data.

Method Summary

Methods

Modifier and Type	Method and Description
DataStorage	convolute(DataStorage x, DataStorage y, long resultSize) Convolutes the two sets of data.

Methods inherited from class org.apfloat.internal.LongModMath

createWTable, getForwardNthRoot, getInverseNthRoot, modDivide, modInverse, modPow, negate

Methods inherited from class org.apfloat.internal.LongElementaryModMath

getModulus, modAdd, modMultiply, modSubtract, setModulus

Methods inherited from class java.lang.Object

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

Constructor Detail

Long3NTTConvolutionStrategy

public Long3NTTConvolutionStrategy(int radix,
                           NTTStrategy transform)

Creates a new convoluter that uses the specified transform for transforming the data.

Parameters:

radix - The radix that will be used.

transform - The transform that will be used.

Method Detail

convolute

public DataStorage convolute(DataStorage x,
                    DataStorage y,
                    long resultSize)
                      throws ApfloatRuntimeException

Description copied from interface: ConvolutionStrategy

Convolutes the two sets of data.

Specified by:

convolute in interface ConvolutionStrategy

Parameters:

x - First data set.

y - Second data set.

resultSize - Number of elements needed in the result data.

Returns:

The convolved data.

Throws:

ApfloatRuntimeException