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 import org.hipparchus.FieldElement;
26
27 /**
28 * Interface defining a visitor for matrix entries.
29 *
30 * @param <T> the type of the field elements
31 */
32 public interface FieldMatrixChangingVisitor<T extends FieldElement<?>> {
33 /**
34 * Start visiting a matrix.
35 * <p>This method is called once before any entry of the matrix is visited.</p>
36 * @param rows number of rows of the matrix
37 * @param columns number of columns of the matrix
38 * @param startRow Initial row index
39 * @param endRow Final row index (inclusive)
40 * @param startColumn Initial column index
41 * @param endColumn Final column index (inclusive)
42 */
43 void start(int rows, int columns,
44 int startRow, int endRow, int startColumn, int endColumn);
45
46 /**
47 * Visit one matrix entry.
48 * @param row row index of the entry
49 * @param column column index of the entry
50 * @param value current value of the entry
51 * @return the new value to be set for the entry
52 */
53 T visit(int row, int column, T value);
54
55 /**
56 * End visiting a matrix.
57 * <p>This method is called once after all entries of the matrix have been visited.</p>
58 * @return the value that the <code>walkInXxxOrder</code> must return
59 */
60 T end();
61 }