org.apfloat.internal
Class LongCRTMath

java.lang.Object
  org.apfloat.internal.LongCRTMath

Direct Known Subclasses:

LongCarryCRT

public class LongCRTMath
extends Object

Basic arithmetic for calculating the Chinese Remainder Theorem. Works for the long type.

Version:

1.1

Author:

Mikko Tommila

Constructor Summary

LongCRTMath(int radix)
Creates a carry-CRT math using the specified radix.

Method Summary

long	add(long[] src, long[] srcDst) Adds three words.
long	compare(long[] src1, long[] src2) Compares three words.
long	divide(long[] srcDst) Divides three words by the base to produce two words.
void	multiply(long[] src, long factor, long[] dst) Multiplies two words by one word to produce a result of three words.
void	subtract(long[] src, long[] srcDst) Subtracts three words.

Methods inherited from class java.lang.Object

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

Constructor Detail

LongCRTMath

public LongCRTMath(int radix)

Creates a carry-CRT math using the specified radix.

Parameters:

radix - The radix that will be used.

Method Detail

multiply

public final void multiply(long[] src,
                           long factor,
                           long[] dst)

Multiplies two words by one word to produce a result of three words. Most significant word is stored first.

Parameters:

src - Source array, first multiplicand.

factor - Second multiplicand.

dst - Destination array.

compare

public final long compare(long[] src1,
                          long[] src2)

Compares three words. Most significant word is stored first.

Parameters:

src1 - First operand.

src2 - Second operand.

Returns:

Less than zero if src1 < src2, greater than zero if src1 > src2 and zero if src1 == src2.

add

public final long add(long[] src,
                      long[] srcDst)

Adds three words. Most significant word is stored first.

Parameters:

src - First operand.

srcDst - Second operand, and destination of the operation.

Returns:

Overflow carry bit.

subtract

public final void subtract(long[] src,
                           long[] srcDst)

Subtracts three words. Most significant word is stored first.

Parameters:

src - First operand.

srcDst - Second operand, and destination of the operation.

divide

public final long divide(long[] srcDst)

Divides three words by the base to produce two words. Most significant word is stored first.

Parameters:

srcDst - Source and destination of the operation.

Returns:

Remainder of the division.