org.tensorics.core.tensor.variance

Class CoContraDimensionPairs

java.lang.Object

org.tensorics.core.tensor.variance.CoContraDimensionPairs

public final class CoContraDimensionPairs
extends java.lang.Object

Provides utility methods related to CoContraDimensionPairs and collections of them.

Method Summary

Modifier and Type	Method and Description
static java.util.Set<java.lang.Class<?>>	allDimensionsIn(java.lang.Iterable<CoContraDimensionPair> pairs) Collects all the dimensions that are contained in at least one of the given pairs, as either left or right dimension.
static java.util.List<CoContraDimensionPair>	chooseOnePerContravariantPart(java.util.List<CoContraDimensionPair> allPairs) Filters the list of pairs in such a way, that only one per contravariant type remains.
static java.util.List<CoContraDimensionPair>	coContraPairsOf(Shape left, Shape right) Searches in the two given shapes for dimensions that form pairs of co- and contravariant dimensions.
static Position	convertToRight(Position position, java.util.List<CoContraDimensionPair> dimensionPairs)
static java.util.Set<java.lang.Class<?>>	leftDimensionsIn(java.lang.Iterable<CoContraDimensionPair> pairs)
static java.util.Map<java.lang.Class<?>,java.util.Collection<CoContraDimensionPair>>	mapOutByContravariantPart(java.util.List<CoContraDimensionPair> allPairs)
static java.util.Set<java.lang.Class<?>>	rightDimensionsIn(java.lang.Iterable<CoContraDimensionPair> pairs)

Methods inherited from class java.lang.Object

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

Method Detail

rightDimensionsIn

public static java.util.Set<java.lang.Class<?>> rightDimensionsIn(java.lang.Iterable<CoContraDimensionPair> pairs)

leftDimensionsIn

public static java.util.Set<java.lang.Class<?>> leftDimensionsIn(java.lang.Iterable<CoContraDimensionPair> pairs)

allDimensionsIn

public static java.util.Set<java.lang.Class<?>> allDimensionsIn(java.lang.Iterable<CoContraDimensionPair> pairs)

Collects all the dimensions that are contained in at least one of the given pairs, as either left or right dimension.

Parameters:

pairs - the pairs from which to retrieve the dimensions

Returns:

all the dimensions which are involved in at least one of the sets

mapOutByContravariantPart

public static java.util.Map<java.lang.Class<?>,java.util.Collection<CoContraDimensionPair>> mapOutByContravariantPart(java.util.List<CoContraDimensionPair> allPairs)

coContraPairsOf

public static java.util.List<CoContraDimensionPair> coContraPairsOf(Shape left,
                                                                    Shape right)

Searches in the two given shapes for dimensions that form pairs of co- and contravariant dimensions. This means that the dimension is either covariant in the left shape and contravariant in the right or the other way around.

Parameters:

left - the left shape of an operation that involves co- contravariant coordinates

right - the right shape of an operation that involves co- and contravariant coordinates

Returns:

a (unfiltered) list of pairs of coordinates, that have have co- and contravariant matches in both shapes.

chooseOnePerContravariantPart

public static java.util.List<CoContraDimensionPair> chooseOnePerContravariantPart(java.util.List<CoContraDimensionPair> allPairs)

Filters the list of pairs in such a way, that only one per contravariant type remains.

Parameters:

allPairs - the pairs to filter

Returns:

a list containing only those, which in the end shall be used

convertToRight

public static Position convertToRight(Position position,
                                      java.util.List<CoContraDimensionPair> dimensionPairs)