Package org.apfloat.internal

Class AbstractStepFNTStrategy

java.lang.Object

org.apfloat.internal.AbstractStepFNTStrategy

All Implemented Interfaces:

Parallelizable, NTTStrategy

Direct Known Subclasses:

SixStepFNTStrategy, TwoPassFNTStrategy

public abstract class AbstractStepFNTStrategy
extends Object
implements NTTStrategy, Parallelizable

Abstract superclass for step-based FNT strategies.

All access to this class must be externally synchronized.

Since:

1.7.0

Version:

1.8.0

Author:

Mikko Tommila

See Also:

• NTTStepStrategy

Field Summary

Fields

Modifier and Type	Field	Description
protected NTTStepStrategy	stepStrategy	The NTT steps.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractStepFNTStrategy()	Subclass constructor.

Method Summary

Modifier and Type	Method	Description
long	getTransformLength(long size)	Return the supported transform length for the specified data size.
protected abstract void	inverseTransform(DataStorage dataStorage, int n1, int n2, long length, long totalTransformLength, int modulus)	Inverse transform the data in steps.
void	inverseTransform(DataStorage dataStorage, int modulus, long totalTransformLength)	Perform an inverse transform on the data.
void	transform(DataStorage dataStorage, int modulus)	Perform a forward transform on the data.
protected abstract void	transform(DataStorage dataStorage, int n1, int n2, long length, int modulus)	Transform the data in steps.

Methods inherited from class java.lang.Object

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

Field Details

stepStrategy

protected NTTStepStrategy stepStrategy

The NTT steps.

Constructor Details

AbstractStepFNTStrategy

protected AbstractStepFNTStrategy()

Subclass constructor.

Method Details

transform

public void transform(DataStorage dataStorage,
 int modulus)
               throws ApfloatRuntimeException

Description copied from interface: NTTStrategy

Perform a forward transform on the data.

Multiple moduli can be used, if the convolution algorithm uses the Chinese Remainder Theorem to calculate the final result.

Specified by:

transform in interface NTTStrategy

Parameters:

dataStorage - The data to be transformed.

modulus - Number of modulus to use (in case the transform supports multiple moduli).

Throws:

ApfloatRuntimeException

inverseTransform

public void inverseTransform(DataStorage dataStorage,
 int modulus,
 long totalTransformLength)
                      throws ApfloatRuntimeException

Description copied from interface: NTTStrategy

Perform an inverse transform on the data.

Multiple moduli can be used, if the convolution algorithm uses the Chinese Remainder Theorem to calculate the final result.

Specified by:

inverseTransform in interface NTTStrategy

Parameters:

dataStorage - The data to be transformed.

modulus - Number of modulus to use (in case the transform supports multiple moduli).

totalTransformLength - Total transform length; the final result elements are divided by this value.

Throws:

ApfloatRuntimeException

getTransformLength

public long getTransformLength(long size)

Description copied from interface: NTTStrategy

Return the supported transform length for the specified data size.

Specified by:

getTransformLength in interface NTTStrategy

Parameters:

size - Length of the data to be transformed.

Returns:

Length of the transform needed by this transform.

transform

protected abstract void transform(DataStorage dataStorage,
 int n1,
 int n2,
 long length,
 int modulus)
                           throws ApfloatRuntimeException

Transform the data in steps.

Parameters:

dataStorage - The data.

n1 - Height of the data matrix.

n2 - Width of the data matrix.

length - Length of the data.

modulus - Which modulus to use.

Throws:

ApfloatRuntimeException

inverseTransform

protected abstract void inverseTransform(DataStorage dataStorage,
 int n1,
 int n2,
 long length,
 long totalTransformLength,
 int modulus)
                                  throws ApfloatRuntimeException

Inverse transform the data in steps.

Parameters:

dataStorage - The data.

n1 - Height of the data matrix.

n2 - Width of the data matrix.

length - Length of the data.

totalTransformLength - Total transform length.

modulus - Which modulus to use.

Throws:

ApfloatRuntimeException