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Diffstat (limited to 'src/main/java/org/apache/commons/math3/optim/linear/LinearOptimizer.java')
-rw-r--r-- | src/main/java/org/apache/commons/math3/optim/linear/LinearOptimizer.java | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/src/main/java/org/apache/commons/math3/optim/linear/LinearOptimizer.java b/src/main/java/org/apache/commons/math3/optim/linear/LinearOptimizer.java new file mode 100644 index 0000000..7e80687 --- /dev/null +++ b/src/main/java/org/apache/commons/math3/optim/linear/LinearOptimizer.java @@ -0,0 +1,131 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.commons.math3.optim.linear; + +import java.util.Collection; +import java.util.Collections; +import org.apache.commons.math3.exception.TooManyIterationsException; +import org.apache.commons.math3.optim.OptimizationData; +import org.apache.commons.math3.optim.PointValuePair; +import org.apache.commons.math3.optim.nonlinear.scalar.MultivariateOptimizer; + +/** + * Base class for implementing linear optimizers. + * + * @since 3.1 + */ +public abstract class LinearOptimizer + extends MultivariateOptimizer { + /** + * Linear objective function. + */ + private LinearObjectiveFunction function; + /** + * Linear constraints. + */ + private Collection<LinearConstraint> linearConstraints; + /** + * Whether to restrict the variables to non-negative values. + */ + private boolean nonNegative; + + /** + * Simple constructor with default settings. + * + */ + protected LinearOptimizer() { + super(null); // No convergence checker. + } + + /** + * @return {@code true} if the variables are restricted to non-negative values. + */ + protected boolean isRestrictedToNonNegative() { + return nonNegative; + } + + /** + * @return the optimization type. + */ + protected LinearObjectiveFunction getFunction() { + return function; + } + + /** + * @return the optimization type. + */ + protected Collection<LinearConstraint> getConstraints() { + return Collections.unmodifiableCollection(linearConstraints); + } + + /** + * {@inheritDoc} + * + * @param optData Optimization data. In addition to those documented in + * {@link MultivariateOptimizer#parseOptimizationData(OptimizationData[]) + * MultivariateOptimizer}, this method will register the following data: + * <ul> + * <li>{@link LinearObjectiveFunction}</li> + * <li>{@link LinearConstraintSet}</li> + * <li>{@link NonNegativeConstraint}</li> + * </ul> + * @return {@inheritDoc} + * @throws TooManyIterationsException if the maximal number of + * iterations is exceeded. + */ + @Override + public PointValuePair optimize(OptimizationData... optData) + throws TooManyIterationsException { + // Set up base class and perform computation. + return super.optimize(optData); + } + + /** + * Scans the list of (required and optional) optimization data that + * characterize the problem. + * + * @param optData Optimization data. + * The following data will be looked for: + * <ul> + * <li>{@link LinearObjectiveFunction}</li> + * <li>{@link LinearConstraintSet}</li> + * <li>{@link NonNegativeConstraint}</li> + * </ul> + */ + @Override + protected void parseOptimizationData(OptimizationData... optData) { + // Allow base class to register its own data. + super.parseOptimizationData(optData); + + // The existing values (as set by the previous call) are reused if + // not provided in the argument list. + for (OptimizationData data : optData) { + if (data instanceof LinearObjectiveFunction) { + function = (LinearObjectiveFunction) data; + continue; + } + if (data instanceof LinearConstraintSet) { + linearConstraints = ((LinearConstraintSet) data).getConstraints(); + continue; + } + if (data instanceof NonNegativeConstraint) { + nonNegative = ((NonNegativeConstraint) data).isRestrictedToNonNegative(); + continue; + } + } + } +} |