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 /**
25 * Marker class for RealVectors that require sparse backing storage
26 * <p>
27 * Caveat: Implementation are allowed to assume that, for any {@code x},
28 * the equality {@code x * 0d == 0d} holds. But it is is not true for
29 * {@code NaN}. Moreover, zero entries will lose their sign.
30 * Some operations (that involve {@code NaN} and/or infinities) may
31 * thus give incorrect results, like multiplications, divisions or
32 * functions mapping.
33 * </p>
34 */
35 public abstract class SparseRealVector extends RealVector {
36
37 /** Empty constructor.
38 * <p>
39 * This constructor is not strictly necessary, but it prevents spurious
40 * javadoc warnings with JDK 18 and later.
41 * </p>
42 * @since 3.0
43 */
44 protected SparseRealVector() { // NOPMD - unnecessary constructor added intentionally to make javadoc happy
45 // nothing to do
46 }
47
48 } // NOPMD - this is an intentional marker class