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 * https://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
18 /*
19 * This is not the original file distributed by the Apache Software Foundation
20 * It has been modified by the Hipparchus project
21 */
22
23 package org.hipparchus.linear;
24
25 /**
26 * Interface defining a visitor for matrix entries.
27 *
28 * @see DefaultRealMatrixChangingVisitor
29 */
30 public interface RealMatrixChangingVisitor {
31 /**
32 * Start visiting a matrix.
33 * <p>This method is called once before any entry of the matrix is visited.</p>
34 * @param rows number of rows of the matrix
35 * @param columns number of columns of the matrix
36 * @param startRow Initial row index
37 * @param endRow Final row index (inclusive)
38 * @param startColumn Initial column index
39 * @param endColumn Final column index (inclusive)
40 */
41 void start(int rows, int columns,
42 int startRow, int endRow, int startColumn, int endColumn);
43
44 /**
45 * Visit one matrix entry.
46 * @param row row index of the entry
47 * @param column column index of the entry
48 * @param value current value of the entry
49 * @return the new value to be set for the entry
50 */
51 double visit(int row, int column, double value);
52
53 /**
54 * End visiting a matrix.
55 * <p>This method is called once after all entries of the matrix have been visited.</p>
56 * @return the value that the <code>walkInXxxOrder</code> must return
57 */
58 double end();
59 }