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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    *      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 32-bit generator suitable for {@code float} generation. This is slightly faster than the
22   * all-purpose generator {@link XoRoShiRo64StarStar}.
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/xoroshiro64star.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 XoRoShiRo64Star 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 XoRoShiRo64Star(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 XoRoShiRo64Star(int seed0, int seed1) {
52          super(seed0, seed1);
53      }
54  
55      /** {@inheritDoc} */
56      @Override
57      protected int nextOutput() {
58          return state0 * 0x9e3779bb;
59      }
60  }