org.apfloat.internal
Class IntConvolutionBuilder

java.lang.Object
  org.apfloat.internal.IntConvolutionBuilder

All Implemented Interfaces:

ConvolutionBuilder

public class IntConvolutionBuilder
extends Object
implements ConvolutionBuilder

Creates convolutions of suitable type for the specified length for the int type.

Based on a work estimate, depending on the operand sizes, the O(n²) long multiplication, Karatsuba multiplication and the NTT algorithms are chosen e.g. as follows:

size1	size2	Algorithm
16	16	Long
16	256	Long
32	32	Long
32	256	Long
64	64	Karatsuba
64	256	NTT
64	65536	Karatsuba
128	128	NTT
128	65536	NTT
128	4294967296	Karatsuba
256	256	NTT
256	4294967296	Karatsuba
512	512	NTT
512	4294967296	NTT

Version:

1.4

Author:

Mikko Tommila

See Also:

IntShortConvolutionStrategy, IntMediumConvolutionStrategy, IntKaratsubaConvolutionStrategy, Int3NTTConvolutionStrategy

Constructor Summary

IntConvolutionBuilder()
Default constructor.

Method Summary

ConvolutionStrategy

createConvolution(int radix, long size1, long size2, long resultSize) Returns a convolution strategy of suitable type for the specified length.

Methods inherited from class java.lang.Object

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

Constructor Detail

IntConvolutionBuilder

public IntConvolutionBuilder()

Default constructor.

Method Detail

createConvolution

public ConvolutionStrategy createConvolution(int radix,
                                             long size1,
                                             long size2,
                                             long resultSize)

Description copied from interface: ConvolutionBuilder

Returns a convolution strategy of suitable type for the specified length.

Specified by:

createConvolution in interface ConvolutionBuilder

Parameters:

radix - The radix that will be used.

size1 - Length of first data set.

size2 - Length of second data set.

resultSize - Minimum number of elements needed in the result data.

Returns:

A suitable object for performing the convolution.