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Java library with basic math stuff

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/**
 * Copyright (C) 2014-2017 Philip Helger (www.helger.com)
 * philip[at]helger[dot]com
 *
 * Licensed 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 com.helger.numbercruncher.mathutils;

/**
 * Compute the machine epsilon for the float and double types, the largest
 * positive floating-point value that, when added to 1, results in a value equal
 * to 1 due to roundoff.
 */
public final class Epsilon
{
  private static final float FLOAT_EPSILON;
  private static final double DOUBLE_EPSILON;

  static
  {
    // Loop to compute the float epsilon value.
    float fTemp = 0.5f;
    while (1 + fTemp > 1)
      fTemp /= 2;
    FLOAT_EPSILON = fTemp;

    // Loop to compute the double epsilon value.
    double dTemp = 0.5;
    while (1 + dTemp > 1)
      dTemp /= 2;
    DOUBLE_EPSILON = dTemp;
  }

  /**
   * Return the float epsilon value.
   *
   * @return the value
   */
  public static float floatValue ()
  {
    return FLOAT_EPSILON;
  }

  /**
   * Return the double epsilon value.
   *
   * @return the value
   */
  public static double doubleValue ()
  {
    return DOUBLE_EPSILON;
  }
}