org.geotools.referencing.operation.transform
Class LogarithmicTransform1D

Object
  Formattable
      AbstractMathTransform
          LogarithmicTransform1D

All Implemented Interfaces:

Serializable, MathTransform, MathTransform1D

public class LogarithmicTransform1D
extends AbstractMathTransform
implements MathTransform1D, Serializable

A one dimensional, logarithmic transform. Input values x are converted into output values y using the following equation:

y = offset + log_base(x) = offset + ln(x)/ln(base)

This transform is the inverse of ExponentialTransform1D.

Since:

2.0

Author:

Martin Desruisseaux (IRD)

See Also:

ExponentialTransform1D, LinearTransform1D, Serialized Form

Nested Class Summary

static class

LogarithmicTransform1D.Provider The provider for the LogarithmicTransform1D.

Nested classes/interfaces inherited from class AbstractMathTransform

AbstractMathTransform.Inverse

Field Summary

double	base The base of the logarithm.
double	offset The offset to add to the logarithm.

Fields inherited from class Formattable

SINGLE_LINE

Constructor Summary

protected

LogarithmicTransform1D(double base, double offset) Constructs a new logarithmic transform.

Method Summary

static MathTransform1D	create(double base, double offset) Constructs a new logarithmic transform.
double	derivative(double value) Gets the derivative of this function at a value.
boolean	equals(Object object) Compares the specified object with this math transform for equality.
ParameterDescriptorGroup	getParameterDescriptors() Returns the parameter descriptors for this math transform.
ParameterValueGroup	getParameterValues() Returns the parameter values for this math transform.
int	getSourceDimensions() Gets the dimension of input points, which is 1.
int	getTargetDimensions() Gets the dimension of output points, which is 1.
int	hashCode() Returns a hash value for this transform.
MathTransform1D	inverse() Creates the inverse transform of this object.
double	transform(double value) Transforms the specified value.
void	transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts) Transforms a list of coordinate point ordinal values.
void	transform(float[] srcPts, int srcOff, float[] dstPts, int dstOff, int numPts) Transforms a list of coordinate point ordinal values.

Methods inherited from class AbstractMathTransform

createTransformedShape, derivative, derivative, ensureNonNull, formatWKT, getName, isIdentity, needCopy, rollLongitude, transform, transform, transform, transform

Methods inherited from class Formattable

cleanupThreadLocals, toString, toWKT, toWKT, toWKT, toWKT

Methods inherited from class Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface MathTransform

derivative, isIdentity, toWKT, transform, transform, transform

Field Detail

base

public final double base

The base of the logarithm.

offset

public final double offset

The offset to add to the logarithm.

Constructor Detail

LogarithmicTransform1D

protected LogarithmicTransform1D(double base,
                                 double offset)

Constructs a new logarithmic transform. This constructor is provided for subclasses only. Instances should be created using the factory method, which may returns optimized implementations for some particular argument values.

Parameters:

base - The base of the logarithm (typically 10).

offset - The offset to add to the logarithm.

Method Detail

create

public static MathTransform1D create(double base,
                                     double offset)

Constructs a new logarithmic transform.

Parameters:

base - The base of the logarithm (typically 10).

offset - The offset to add to the logarithm.

Returns:

The math transform.

getParameterDescriptors

public ParameterDescriptorGroup getParameterDescriptors()

Returns the parameter descriptors for this math transform.

Overrides:

getParameterDescriptors in class AbstractMathTransform

Returns:

The parameter descriptors for this math transform, or null.

See Also:

OperationMethod.getParameters()

getParameterValues

public ParameterValueGroup getParameterValues()

Returns the parameter values for this math transform.

Overrides:

getParameterValues in class AbstractMathTransform

Returns:

A copy of the parameter values for this math transform.

See Also:

Operation.getParameterValues()

getSourceDimensions

public int getSourceDimensions()

Gets the dimension of input points, which is 1.

Specified by:

getSourceDimensions in interface MathTransform

Specified by:

getSourceDimensions in class AbstractMathTransform

Returns:

The dimension of input points.

getTargetDimensions

public int getTargetDimensions()

Gets the dimension of output points, which is 1.

Specified by:

getTargetDimensions in interface MathTransform

Specified by:

getTargetDimensions in class AbstractMathTransform

Returns:

The dimension of output points.

inverse

public MathTransform1D inverse()

Creates the inverse transform of this object.

Specified by:

inverse in interface MathTransform

Specified by:

inverse in interface MathTransform1D

Overrides:

inverse in class AbstractMathTransform

Returns:

The inverse transform.

derivative

public double derivative(double value)

Gets the derivative of this function at a value.

Specified by:

derivative in interface MathTransform1D

Parameters:

value - The value where to evaluate the derivative.

Returns:

The derivative at the specified point.

transform

public double transform(double value)

Transforms the specified value.

Specified by:

transform in interface MathTransform1D

Parameters:

value - The value to transform.

Returns:

the transformed value.

transform

public void transform(float[] srcPts,
                      int srcOff,
                      float[] dstPts,
                      int dstOff,
                      int numPts)

Transforms a list of coordinate point ordinal values.

Specified by:

transform in interface MathTransform

Overrides:

transform in class AbstractMathTransform

Parameters:

srcPts - the array containing the source point coordinates.

srcOff - the offset to the first point to be transformed in the source array.

dstPts - the array into which the transformed point coordinates are returned. May be the same than srcPts.

dstOff - the offset to the location of the first transformed point that is stored in the destination array.

numPts - the number of point objects to be transformed.

transform

public void transform(double[] srcPts,
                      int srcOff,
                      double[] dstPts,
                      int dstOff,
                      int numPts)

Transforms a list of coordinate point ordinal values.

Specified by:

transform in interface MathTransform

Parameters:

srcPts - the array containing the source point coordinates.

srcOff - the offset to the first point to be transformed in the source array.

dstPts - the array into which the transformed point coordinates are returned. May be the same than srcPts.

dstOff - the offset to the location of the first transformed point that is stored in the destination array.

numPts - the number of point objects to be transformed.

hashCode

public int hashCode()

Returns a hash value for this transform. This value need not remain consistent between different implementations of the same class.

Overrides:

hashCode in class AbstractMathTransform

equals

public boolean equals(Object object)

Compares the specified object with this math transform for equality.

Overrides:

equals in class AbstractMathTransform

Parameters:

object - The object to compare with this transform.

Returns:

true if the given object is a transform of the same class and if, given identical source position, the transformed position would be the equals.