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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.commons.math.random;
+
+import org.apache.commons.math.util.FastMath;
+
+/**
+ * This class implements a normalized uniform random generator.
+ * <p>Since it is a normalized random generator, it generates values
+ * from a uniform distribution with mean equal to 0 and standard
+ * deviation equal to 1. Generated values fall in the range
+ * [-&#x0221A;3, +&#x0221A;3].</p>
+ *
+ * @since 1.2
+ *
+ * @version $Revision: 990655 $ $Date: 2010-08-29 23:49:40 +0200 (dim. 29 août 2010) $
+ */
+
+public class UniformRandomGenerator implements NormalizedRandomGenerator {
+
+ /** Serializable version identifier. */
+ private static final long serialVersionUID = 1569292426375546027L;
+
+ /** Square root of three. */
+ private static final double SQRT3 = FastMath.sqrt(3.0);
+
+ /** Underlying generator. */
+ private final RandomGenerator generator;
+
+ /** Create a new generator.
+ * @param generator underlying random generator to use
+ */
+ public UniformRandomGenerator(RandomGenerator generator) {
+ this.generator = generator;
+ }
+
+ /** Generate a random scalar with null mean and unit standard deviation.
+ * <p>The number generated is uniformly distributed between -&sqrt;(3)
+ * and +&sqrt;(3).</p>
+ * @return a random scalar with null mean and unit standard deviation
+ */
+ public double nextNormalizedDouble() {
+ return SQRT3 * (2 * generator.nextDouble() - 1.0);
+ }
+
+}