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 * http://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 package org.apache.commons.rng.core.source32;
19
20 /**
21 * A fast all-purpose 32-bit generator. For faster generation of {@code float} values try the
22 * {@link XoRoShiRo64Star} generator.
23 *
24 * <p>This is a member of the Xor-Shift-Rotate family of generators. Memory footprint is 64
25 * bits.</p>
26 *
27 * @see <a href="http://xoshiro.di.unimi.it/xoroshiro64starstar.c">Original source code</a>
28 * @see <a href="http://xoshiro.di.unimi.it/">xorshiro / xoroshiro generators</a>
29 * @since 1.3
30 */
31 public class XoRoShiRo64StarStar extends AbstractXoRoShiRo64 {
32 /**
33 * Creates a new instance.
34 *
35 * @param seed Initial seed.
36 * If the length is larger than 2, only the first 2 elements will
37 * be used; if smaller, the remaining elements will be automatically
38 * set. A seed containing all zeros will create a non-functional generator.
39 */
40 public XoRoShiRo64StarStar(int[] seed) {
41 super(seed);
42 }
43
44 /**
45 * Creates a new instance using a 2 element seed.
46 * A seed containing all zeros will create a non-functional generator.
47 *
48 * @param seed0 Initial seed element 0.
49 * @param seed1 Initial seed element 1.
50 */
51 public XoRoShiRo64StarStar(int seed0, int seed1) {
52 super(seed0, seed1);
53 }
54
55 /** {@inheritDoc} */
56 @Override
57 protected int nextOutput() {
58 return Integer.rotateLeft(state0 * 0x9e3779bb, 5) * 5;
59 }
60 }