Package org.apache.sis.referencing.operation.projection

Class AlbersEqualArea

Object

FormattableObject

AbstractMathTransform

AbstractMathTransform2D

NormalizedProjection

AlbersEqualArea

All Implemented Interfaces:

Serializable, Parameterized, Lenient­Comparable, Math­Transform, Math­Transform2D

public class AlbersEqualArea
extends NormalizedProjection

Albers Equal Area projection (EPSG code 9822). See the following references for an overview:

• Albers projection on Wikipedia
• Albers Equal-Area Conic projection on MathWorld

The "standard_parallel_2" parameter is optional and will be given the same value as "standard_parallel_1" if not set.

Since:

0.8

See Also:

• Serialized Form

Defined in the sis-referencing module

Nested Class Summary

Nested classes/interfaces inherited from class NormalizedProjection

Normalized­Projection.Parameter­Role

Field Summary

Fields inherited from class NormalizedProjection

eccentricity, eccentricity­Squared

Constructor Summary

Constructors

Constructor	Description
Albers­Equal­Area(Operation­Method method, Parameters parameters)	Creates an Albers Equal Area projection from the given parameters.

Method Summary

Modifier and Type	Method	Description
Math­Transform	create­Map­Projection(Math­Transform­Factory factory)	Returns the sequence of normalization → this → denormalization transforms as a whole.
protected void	inverse­Transform(double[] src­Pts, int src­Off, double[] dst­Pts, int dst­Off)	Converts the specified (x,y) coordinates and stores the (θ,φ) result in dst­Pts.
Matrix	transform(double[] src­Pts, int src­Off, double[] dst­Pts, int dst­Off, boolean derivate)	Converts the specified (θ,φ) coordinate (units in radians) and stores the result in dst­Pts.

Methods inherited from class NormalizedProjection

compute­Hash­Code, equals, get­Contextual­Parameters, get­Parameter­Descriptors, get­Parameter­Values, inverse, try­Concatenate

Methods inherited from class AbstractMathTransform2D

create­Transformed­Shape, derivative, get­Source­Dimensions, get­Target­Dimensions, transform

Methods inherited from class AbstractMathTransform

derivative, equals, format­To, hash­Code, is­Identity, transform, transform, transform, transform, transform

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 MathTransform

derivative, is­Identity, to­WKT, transform, transform, transform, transform, transform

Constructor Details

AlbersEqualArea

public AlbersEqualArea(OperationMethod method,
 Parameters parameters)

Creates an Albers Equal Area projection from the given parameters.

Parameters:

method - description of the projection parameters.

parameters - the parameter values of the projection to create.

Method Details

createMapProjection

public MathTransform createMapProjection(MathTransformFactory factory)
                                  throws FactoryException

Returns the sequence of normalization → this → denormalization transforms as a whole. The transform returned by this method expects (longitude, latitude) coordinates in degrees and returns (x,y) coordinates in metres.

The non-linear part of the returned transform will be this transform, except if the ellipsoid is spherical. In the later case, this transform will be replaced by a simplified implementation.

Overrides:

create­Map­Projection in class Normalized­Projection

Parameters:

factory - The factory to use for creating the transform.

Returns:

the map projection from (λ,φ) to (x,y) coordinates.

Throws:

Factory­Exception - if an error occurred while creating a transform.

See Also:

• Contextual­Parameters.complete­Transform(Math­Transform­Factory, Math­Transform)

transform

public Matrix transform(double[] srcPts,
 int srcOff,
 double[] dstPts,
 int dstOff,
 boolean derivate)
                 throws ProjectionException

Converts the specified (θ,φ) coordinate (units in radians) and stores the result in dst­Pts. In addition, opportunistically computes the projection derivative if derivate is true.

Specified by:

transform in class Normalized­Projection

Parameters:

src­Pts - the array containing the source point coordinate, as (longitude, latitude) angles in radians.

src­Off - the offset of the single coordinate to be converted in the source array.

dst­Pts - the array into which the converted coordinate is returned (may be the same than src­Pts). Coordinates will be expressed in a dimensionless unit, as a linear distance on a unit sphere or ellipse.

dst­Off - the offset of the location of the converted coordinate that is stored in the destination array.

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

Returns:

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

Throws:

Projection­Exception - if the coordinate can not be converted.

See Also:

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

inverseTransform

protected void inverseTransform(double[] srcPts,
 int srcOff,
 double[] dstPts,
 int dstOff)
                         throws ProjectionException

Converts the specified (x,y) coordinates and stores the (θ,φ) result in dst­Pts.

Specified by:

inverse­Transform in class Normalized­Projection

Parameters:

src­Pts - the array containing the source point coordinate, as linear distance on a unit sphere or ellipse.

src­Off - the offset of the point to be converted in the source array.

dst­Pts - the array into which the converted point coordinate is returned (may be the same than src­Pts). Coordinates will be (longitude, latitude) angles in radians.

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

Throws:

Projection­Exception - if the point can not be converted.