1/* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18package org.apache.commons.math.optimization.linear; 19 20/** 21 * Types of relationships between two cells in a Solver {@link LinearConstraint}. 22 * @version $Revision: 1003886 $ $Date: 2010-10-02 23:04:44 +0200 (sam. 02 oct. 2010) $ 23 * @since 2.0 24 */ 25public enum Relationship { 26 27 /** Equality relationship. */ 28 EQ("="), 29 30 /** Lesser than or equal relationship. */ 31 LEQ("<="), 32 33 /** Greater than or equal relationship. */ 34 GEQ(">="); 35 36 /** Display string for the relationship. */ 37 private final String stringValue; 38 39 /** Simple constructor. 40 * @param stringValue display string for the relationship 41 */ 42 private Relationship(String stringValue) { 43 this.stringValue = stringValue; 44 } 45 46 /** {@inheritDoc} */ 47 @Override 48 public String toString() { 49 return stringValue; 50 } 51 52 /** 53 * Get the relationship obtained when multiplying all coefficients by -1. 54 * @return relationship obtained when multiplying all coefficients by -1 55 */ 56 public Relationship oppositeRelationship() { 57 switch (this) { 58 case LEQ : 59 return GEQ; 60 case GEQ : 61 return LEQ; 62 default : 63 return EQ; 64 } 65 } 66 67} 68