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 package org.apache.commons.math3.optim.linear; 18 19 import org.apache.commons.math3.optim.OptimizationData; 20 21 /** 22 * Pivot selection rule to the use for a Simplex solver. 23 * 24 * @since 3.3 25 */ 26 public enum PivotSelectionRule implements OptimizationData { 27 /** 28 * The classical rule, the variable with the most negative coefficient 29 * in the objective function row will be chosen as entering variable. 30 */ 31 DANTZIG, 32 /** 33 * The first variable with a negative coefficient in the objective function 34 * row will be chosen as entering variable. This rule guarantees to prevent 35 * cycles, but may take longer to find an optimal solution. 36 */ 37 BLAND 38 } 39