Package org.apfloat.internal

Class LongNTTConvolutionStepStrategy

java.lang.Object

org.apfloat.internal.LongElementaryModMath

org.apfloat.internal.LongModMath

org.apfloat.internal.LongNTTConvolutionStepStrategy

All Implemented Interfaces:

Parallelizable, NTTConvolutionStepStrategy

public class LongNTTConvolutionStepStrategy
extends LongModMath
implements NTTConvolutionStepStrategy, Parallelizable

Steps of a three-NTT convolution for the long type. This class implements the details of the element-by-element multiplication and element-by-element squaring of the transformed elements.

The in-place multiplication and 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.

Since:

1.7.0

Version:

1.9.0

Author:

Mikko Tommila

Constructor Summary

Constructors

Constructor	Description
LongNTTConvolutionStepStrategy()	Default constructor.

Method Summary

Modifier and Type	Method	Description
protected ParallelRunnable	createMultiplyInPlaceParallelRunnable(DataStorage sourceAndDestination, DataStorage source, int modulus)	Create a ParallelRunnable for multiplying the elements in-place.
protected ParallelRunnable	createSquareInPlaceParallelRunnable(DataStorage sourceAndDestination, int modulus)	Create a ParallelRunnable for squaring the elements in-place.
void	multiplyInPlace(DataStorage sourceAndDestination, DataStorage source, int modulus)	Linear multiplication in the number theoretic domain.
void	squareInPlace(DataStorage sourceAndDestination, int modulus)	Linear squaring in the number theoretic domain.

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 Details

LongNTTConvolutionStepStrategy

public LongNTTConvolutionStepStrategy()

Default constructor.

Method Details

multiplyInPlace

public void multiplyInPlace(DataStorage sourceAndDestination,
 DataStorage source,
 int modulus)
                     throws ApfloatRuntimeException

Description copied from interface: NTTConvolutionStepStrategy

Linear multiplication in the number theoretic domain. The operation is sourceAndDestination[i] *= source[i] (mod m).

For maximum performance, sourceAndDestination should be in memory if possible.

Specified by:

multiplyInPlace in interface NTTConvolutionStepStrategy

Parameters:

sourceAndDestination - The first source data storage, which is also the destination.

source - The second source data storage.

modulus - Which modulus to use (0, 1, 2)

Throws:

ApfloatRuntimeException

squareInPlace

public void squareInPlace(DataStorage sourceAndDestination,
 int modulus)
                   throws ApfloatRuntimeException

Description copied from interface: NTTConvolutionStepStrategy

Linear squaring in the number theoretic domain. The operation is sourceAndDestination[i] *= sourceAndDestination[i] (mod m).

For maximum performance, sourceAndDestination should be in memory if possible.

Specified by:

squareInPlace in interface NTTConvolutionStepStrategy

Parameters:

sourceAndDestination - The source data storage, which is also the destination.

modulus - Which modulus to use (0, 1, 2)

Throws:

ApfloatRuntimeException

createMultiplyInPlaceParallelRunnable

protected ParallelRunnable createMultiplyInPlaceParallelRunnable(DataStorage sourceAndDestination,
 DataStorage source,
 int modulus)

Create a ParallelRunnable for multiplying the elements in-place.

Parameters:

sourceAndDestination - The first source data storage, which is also the destination.

source - The second source data storage.

modulus - Which modulus to use (0, 1, 2)

Returns:

An object suitable for multiplying the elements in parallel.

createSquareInPlaceParallelRunnable

protected ParallelRunnable createSquareInPlaceParallelRunnable(DataStorage sourceAndDestination,
 int modulus)

Create a ParallelRunnable for squaring the elements in-place.

Parameters:

sourceAndDestination - The source data storage, which is also the destination.

modulus - Which modulus to use (0, 1, 2)

Returns:

An object suitable for squaring the elements in parallel.