fast Inverse Sqrt - Java java.lang

Java examples for java.lang:Math Function

  1. HOME
  2. Java
  3. java.lang
  4. Math Function

Description

fast Inverse Sqrt

Demo Code

/*/*from w  w w. j  a v  a  2  s  .  com*/
 * Copyright (c) 2006-2011 Karsten Schmidt
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * http://creativecommons.org/licenses/LGPL/2.1/
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
//package com.java2s;

public class Main {
    public static final float fastInverseSqrt(float x) {
        float half = 0.5F * x;
        int i = Float.floatToIntBits(x);
        i = 0x5f375a86 - (i >> 1);
        x = Float.intBitsToFloat(i);
        return x * (1.5F - half * x * x);
    }
}

Related Tutorials