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High performance arbitrary precision arithmetic library

There is a newer version: 1.14.0

package org.apfloat.spi;

import org.apfloat.ApfloatRuntimeException;

/**
 * Interface for performing the steps of a carry-CRT operation in a convolution.
 *
 * @param  The element array type of the carry-CRT steps.
 *
 * @since 1.7.0
 * @version 1.7.0
 * @author Mikko Tommila
 */

public interface CarryCRTStepStrategy
{
    /**
     * Perform the Chinese Remainder Theorem (CRT) on each element
     * of the three result data sets to get the result of each element
     * modulo the product of the three moduli. Then it calculates the carries
     * for the block of data to get the final result.
     *
     * Note that the return value's initial word may be zero or non-zero,
     * depending on how large the result is.
     *
     * Assumes that MODULUS[0] > MODULUS[1] > MODULUS[2].
     *
     * @param resultMod0 The result modulo MODULUS[0].
     * @param resultMod1 The result modulo MODULUS[1].
     * @param resultMod2 The result modulo MODULUS[2].
     * @param dataStorage The destination data storage of the computation.
     * @param size The number of elements in the whole data set.
     * @param resultSize The number of elements needed in the final result.
     * @param offset The offset within the data for the block to be computed.
     * @param length Length of the block to be computed.
     *
     * @return The carries overflowing from this block (two elements).
     */

    public T crt(DataStorage resultMod0, DataStorage resultMod1, DataStorage resultMod2, DataStorage dataStorage, long size, long resultSize, long offset, long length)
        throws ApfloatRuntimeException;

    /**
     * Propagate carries from the previous block computed with the CRT
     * method.
     *
     * @param dataStorage The destination data storage of the computation.
     * @param size The number of elements in the whole data set.
     * @param resultSize The number of elements needed in the final result.
     * @param offset The offset within the data for the block to be computed.
     * @param length Length of the block to be computed.
     * @param results The carry overflow from this block (two elements).
     * @param previousResults The carry overflow from the previous block (two elements).
     *
     * @return The carries overflowing from this block (two elements).
     */

    public T carry(DataStorage dataStorage, long size, long resultSize, long offset, long length, T results, T previousResults)
        throws ApfloatRuntimeException;
}