Class CartesianToPolar

java.lang.Object

org.apache.sis.io.wkt.FormattableObject

org.apache.sis.referencing.operation.transform.AbstractMathTransform

org.apache.sis.referencing.operation.transform.CoordinateSystemTransform

org.apache.sis.referencing.operation.transform.CartesianToPolar

All Implemented Interfaces:

Serializable, Parameterized, LenientComparable, org.opengis.referencing.operation.MathTransform

final class CartesianToPolar
extends CoordinateSystemTransform
implements Serializable

Conversions from two-dimensional Cartesian coordinates to polar coordinates. This conversion assumes that there is no datum change.

See PolarToCartesian for explanation on axes convention. Axis order shall match the order defined by Normalizer in org.apache.sis.referencing.cs package.

Note: We do not provide explicit CartesianToCylindrical implementation. Instead, the cylindrical case is implemented by the polar case with a PassThroughTransform for the height. This allows Apache SIS to use the optimization implemented by PassThroughTransform when for example a concatenated transform is dropping the z axis.

Since:

0.7

Version:

0.7

Nested Class Summary

Nested classes/interfaces inherited from class AbstractMathTransform

AbstractMathTransform.Inverse

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static final CartesianToPolar	INSTANCE	The singleton instance computing output coordinates are in radians.
private static final long	serialVersionUID	For cross-version compatibility.

Fields inherited from class CoordinateSystemTransform

context

Fields inherited from class AbstractMathTransform

MAXIMUM_BUFFER_SIZE, MAXIMUM_FAILURES

Constructor Summary

Constructors

Modifier	Constructor	Description
private	CartesianToPolar()	Creates the singleton instance.

Method Summary

Modifier and Type	Method	Description
org.opengis.referencing.operation.MathTransform	inverse()	Returns the inverse of this transform.
private Object	readResolve()	Returns the singleton instance on deserialization.
org.opengis.referencing.operation.Matrix	transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, boolean derivate)	Converts a single coordinate and optionally computes the derivative.
void	transform(double[] srcPts, int srcOff, double[] dstPts, int dstOff, int numPts)	Converts an array of coordinates.

Methods inherited from class CoordinateSystemTransform

completeTransform, create, getContextualParameters, getParameterValues, getSourceDimensions, getTargetDimensions, passthrough

Methods inherited from class AbstractMathTransform

beforeFormat, computeHashCode, derivative, equals, equals, formatTo, getDomain, getParameterDescriptors, hashCode, isIdentity, isInverseEquals, mismatchedDimension, transform, transform, transform, transform, tryConcatenate

Methods inherited from class FormattableObject

print, toString, toString, toWKT

Methods inherited from class Object

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

Methods inherited from interface org.opengis.referencing.operation.MathTransform

toWKT

Field Details

serialVersionUID

private static final long serialVersionUID

For cross-version compatibility.

See Also:

• Constant Field Values

INSTANCE

static final CartesianToPolar INSTANCE

The singleton instance computing output coordinates are in radians. For the instance computing output coordinates in degrees, use CoordinateSystemTransform.create(MathTransformFactory, CoordinateSystem, CoordinateSystem, ThreadLocal) instead.

Constructor Details

CartesianToPolar

private CartesianToPolar()

Creates the singleton instance. Output coordinates are in radians.

Method Details

readResolve

private Object readResolve()
                    throws ObjectStreamException

Returns the singleton instance on deserialization.

Throws:

ObjectStreamException

inverse

public org.opengis.referencing.operation.MathTransform inverse()

Returns the inverse of this transform.

Specified by:

inverse in interface org.opengis.referencing.operation.MathTransform

Overrides:

inverse in class AbstractMathTransform

transform

public org.opengis.referencing.operation.Matrix transform(double[] srcPts,
 int srcOff,
 double[] dstPts,
 int dstOff,
 boolean derivate)

Converts a single coordinate and optionally computes the derivative.

Specified by:

transform in class AbstractMathTransform

Parameters:

srcPts - the array containing the source coordinates (cannot be null).

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

dstPts - the array into which the transformed coordinates is returned. May be the same than srcPts. May be null if only the derivative matrix is desired.

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

derivate - true for computing the derivative, or false if not needed.

Returns:

the matrix of the transform derivative at the given source position, or null if the derivate argument is false.

See Also:

• AbstractMathTransform.derivative(DirectPosition)
• AbstractMathTransform.transform(DirectPosition, DirectPosition)
• MathTransforms.derivativeAndTransform(MathTransform, double[], int, double[], int)

transform

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

Converts an array of coordinates. This method performs the same conversion than transform(double[], int, double[], int, boolean), but the formulas are repeated here for performance reasons.

Specified by:

transform in interface org.opengis.referencing.operation.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.