/*
 * Created on Jun 30, 2005
 */
/*
 * Copyright (c) 2005-2006 Gregor Heinrich. All rights reserved. Redistribution and
 * use in source and binary forms, with or without modification, are permitted
 * provided that the following conditions are met: 1. Redistributions of source
 * code must retain the above copyright notice, this list of conditions and the
 * following disclaimer. 2. Redistributions in binary form must reproduce the
 * above copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the distribution.
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESSED OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.knowceans.util;

/**
 * DigitFormat formats double numbers into a specified digit format.
 * 
 * @author heinrich
 */
public class DigitFormat {

    public static void main(String[] args) {
        System.out.println(DigitFormat.format(100, 2));
    }

    public static double format(double x, int ndigits) {
        if (x == 0)
            return 0;
        int magnitude = (int) (Math.log(x) / Math.log(10));
        double factor = Math.pow(10, ndigits - 1 - magnitude);
        double y = Math.round(x * factor) / factor;

        return y;
    }
}
