001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.math3.geometry.partitioning; 018 019import org.apache.commons.math3.geometry.Point; 020import org.apache.commons.math3.geometry.Space; 021 022/** This interface defines mappers between a space and one of its sub-spaces. 023 024 * <p>Sub-spaces are the lower dimensions subsets of a n-dimensions 025 * space. The (n-1)-dimension sub-spaces are specific sub-spaces known 026 * as {@link Hyperplane hyperplanes}. This interface can be used regardless 027 * of the dimensions differences. As an example, {@link 028 * org.apache.commons.math3.geometry.euclidean.threed.Line Line} in 3D 029 * implements Embedding<{@link 030 * org.apache.commons.math3.geometry.euclidean.threed.Vector3D Vector3D}, {link 031 * org.apache.commons.math3.geometry.euclidean.oned.Vector1D Vector1D>, i.e. it 032 * maps directly dimensions 3 and 1.</p> 033 034 * <p>In the 3D euclidean space, hyperplanes are 2D planes, and the 1D 035 * sub-spaces are lines.</p> 036 037 * <p> 038 * Note that this interface is <em>not</em> intended to be implemented 039 * by Apache Commons Math users, it is only intended to be implemented 040 * within the library itself. New methods may be added even for minor 041 * versions, which breaks compatibility for external implementations. 042 * </p> 043 044 * @param <S> Type of the embedding space. 045 * @param <T> Type of the embedded sub-space. 046 047 * @see Hyperplane 048 * @since 3.0 049 */ 050public interface Embedding<S extends Space, T extends Space> { 051 052 /** Transform a space point into a sub-space point. 053 * @param point n-dimension point of the space 054 * @return (n-1)-dimension point of the sub-space corresponding to 055 * the specified space point 056 * @see #toSpace 057 */ 058 Point<T> toSubSpace(Point<S> point); 059 060 /** Transform a sub-space point into a space point. 061 * @param point (n-1)-dimension point of the sub-space 062 * @return n-dimension point of the space corresponding to the 063 * specified sub-space point 064 * @see #toSubSpace 065 */ 066 Point<S> toSpace(Point<T> point); 067 068}