net.mumie.mathletfactory.math.geom.projective

Class ProjectiveSpace

java.lang.Object

net.mumie.mathletfactory.math.geom.projective.ProjectiveSpace

All Implemented Interfaces:

GeometryIF, NumberTypeDependentIF

Direct Known Subclasses:

ProjectivePoint

public class ProjectiveSpace
extends java.lang.Object
implements GeometryIF

This implements PC(n) if the underlying number field is C and all its projective subspaces in addition it includes the standard affine space associated with it for the moment only two dimensional space is implemented...

Author:

vossbeck

Document status:

finished

Field Summary

Fields

Modifier and Type	Field and Description
protected NumberVectorSpace	m_vectorspace

Fields inherited from interface net.mumie.mathletfactory.math.geom.GeometryIF

AFFINE_GEOMETRY, AFFINE2D_GEOMETRY, AFFINE3D_GEOMETRY, EUCLIDEAN2D_GEOMETRY, EUCLIDEAN3D_GEOMETRY, HYPERBOLIC2D_GEOMETRY, NO_GEOMETRY_TYPE, PROJECTIVEND_GEOMETRY

Constructor Summary

Constructors

Constructor and Description
ProjectiveSpace(java.lang.Class entryClass, int dim, int extDim) Creates an ProjectiveSpace with all data based on numbers with class type entryClass.
ProjectiveSpace(NumberTuple projPointCoord) Creates a zero dimensional ProjectiveSpace (that is in fact a point), with environmental dimension equal to the dimension of the projPointCoord minus one.
ProjectiveSpace(NumberVectorSpace aVecSpace)
ProjectiveSpace(ProjectiveSpace[] spacev)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(ProjectiveSpace aSpace)
NumberTuple[]	getAffineBasis()
NumberMatrix	getBasisMatrixRef()
int	getDimension() Returns the internal dimension of this ProjectiveSpace, which would be 0 for a point, 1 for a line, ...
int	getEnvDimension() Returns the environmental space dimension of this ProjectiveSpace.
int	getGeomType() Returns the geometry type of the current geometric object.
java.lang.Class	getNumberClass() Returns the class type of the underlying number class (currently something like MDouble.class, MRational.class, ...)
NumberTuple[]	getProjectiveBasis() Returns the basis vector array of the underlying NumberVectorSpace of this ProjectiveSpace.
GeometryIF	groupAction(GroupElementIF g) Shouldn't this method call m_vectorspace.groupAction()?
ProjectiveSpace	intersected(ProjectiveSpace aProjectiveSpace) This computes the intersection of ProjectiveSpace with aProjectiveSpace and afterwards returned by this method.
boolean	isInfinite()
protected boolean	isValidAffineCoordinateIndex(int i)
ProjectiveSpace	setAffineBasis(NumberTuple[] coord)
ProjectiveSpace	setProjectiveBasis(NumberTuple[] projCoordBasis) Sets the basis of the underlying NumberVectorSpace to projCoordBasis.

Methods inherited from class java.lang.Object

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

Field Detail

m_vectorspace

protected NumberVectorSpace m_vectorspace

Constructor Detail

ProjectiveSpace

public ProjectiveSpace(java.lang.Class entryClass,
               int dim,
               int extDim)

Creates an ProjectiveSpace with all data based on numbers with class type entryClass. dim defines the dimension of this ProjectiveSpace, i.e. a zero dimensional space would be a projective point, a one dimensional space would be a projective line, ... extDim describes the dimension of the environmental space.

ProjectiveSpace

public ProjectiveSpace(NumberVectorSpace aVecSpace)

ProjectiveSpace

public ProjectiveSpace(ProjectiveSpace[] spacev)

ProjectiveSpace

public ProjectiveSpace(NumberTuple projPointCoord)

Creates a zero dimensional ProjectiveSpace (that is in fact a point), with environmental dimension equal to the dimension of the projPointCoord minus one.

Method Detail

equals

public boolean equals(ProjectiveSpace aSpace)

intersected

public ProjectiveSpace intersected(ProjectiveSpace aProjectiveSpace)

This computes the intersection of ProjectiveSpace with aProjectiveSpace and afterwards returned by this method. This and aProjectiveSpace remain unchanged

getGeomType

public int getGeomType()

Description copied from interface: GeometryIF

Returns the geometry type of the current geometric object. Those types are defined as static final variables in GeometryIF.

Specified by:

getGeomType in interface GeometryIF

isInfinite

public boolean isInfinite()

getDimension

public int getDimension()

Returns the internal dimension of this ProjectiveSpace, which would be 0 for a point, 1 for a line, ...

getEnvDimension

public int getEnvDimension()

Returns the environmental space dimension of this ProjectiveSpace. Observe: If an element of this ProjectiveSpace is defined by (n+1) homogeneous coordinates, the returned environmental dimension is n.

groupAction

public GeometryIF groupAction(GroupElementIF g)

Shouldn't this method call m_vectorspace.groupAction()? This would not work in the current version, because NumberVectorSpace.groupAction() uses the actual basis, whereas ProjectiveSpace.setProjectiveBasis() calls NumberVectorSpace.setDefaultBasis()!

Specified by:

groupAction in interface GeometryIF

getProjectiveBasis

public NumberTuple[] getProjectiveBasis()

Returns the basis vector array of the underlying NumberVectorSpace of this ProjectiveSpace. This method has side effects: Working on the data of the returned vectors will affect this ProjectiveSpace also.

setProjectiveBasis

public ProjectiveSpace setProjectiveBasis(NumberTuple[] projCoordBasis)

Sets the basis of the underlying NumberVectorSpace to projCoordBasis. It is expected that the elements in projCoordBasis are linearly independent.

setAffineBasis

public ProjectiveSpace setAffineBasis(NumberTuple[] coord)

getAffineBasis

public NumberTuple[] getAffineBasis()

getNumberClass

public java.lang.Class getNumberClass()

Returns the class type of the underlying number class (currently something like MDouble.class, MRational.class, ...)

Specified by:

getNumberClass in interface NumberTypeDependentIF

isValidAffineCoordinateIndex

protected boolean isValidAffineCoordinateIndex(int i)

getBasisMatrixRef

public NumberMatrix getBasisMatrixRef()