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 */
017
018package org.apache.commons.math3.linear;
019
020/**
021 * Default implementation of the {@link RealMatrixChangingVisitor} interface.
022 * <p>
023 * This class is a convenience to create custom visitors without defining all
024 * methods. This class provides default implementations that do nothing.
025 * </p>
026 *
027 * @since 2.0
028 */
029public class DefaultRealMatrixChangingVisitor implements RealMatrixChangingVisitor {
030    /** {@inheritDoc} */
031    public void start(int rows, int columns,
032                      int startRow, int endRow, int startColumn, int endColumn) {
033    }
034
035    /** {@inheritDoc} */
036    public double visit(int row, int column, double value) {
037        return value;
038    }
039
040    /** {@inheritDoc} */
041    public double end() {
042        return 0;
043    }
044}