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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  package org.hipparchus.linear;
23  
24  import org.hipparchus.exception.MathIllegalArgumentException;
25  import org.junit.jupiter.api.Test;
26  
27  import static org.junit.jupiter.api.Assertions.assertEquals;
28  import static org.junit.jupiter.api.Assertions.assertThrows;
29  
30  final class OpenMapRealMatrixTest {
31  
32      @Test
33      void testMath679() {
34          assertThrows(MathIllegalArgumentException.class, () -> {
35              new OpenMapRealMatrix(3, Integer.MAX_VALUE);
36          });
37      }
38  
39      @Test
40      void testMath870() {
41          // Caveat: This implementation assumes that, for any {@code x},
42          // the equality {@code x * 0d == 0d} holds. But it is is not true for
43          // {@code NaN}. Moreover, zero entries will lose their sign.
44          // Some operations (that involve {@code NaN} and/or infinities) may
45          // thus give incorrect results.
46          OpenMapRealMatrix a = new OpenMapRealMatrix(3, 3);
47          OpenMapRealMatrix x = new OpenMapRealMatrix(3, 1);
48          x.setEntry(0, 0, Double.NaN);
49          x.setEntry(2, 0, Double.NEGATIVE_INFINITY);
50          OpenMapRealMatrix b = a.multiply(x);
51          for (int i = 0; i < b.getRowDimension(); ++i) {
52              for (int j = 0; j < b.getColumnDimension(); ++j) {
53                  // NaNs and infinities have disappeared, this is a limitation of our implementation
54                  assertEquals(0.0, b.getEntry(i, j), 1.0e-20);
55              }
56          }
57      }
58  }