Map one range into another.

RangeMapping.java

/**
 * @since 04/07/2013
 * @author dvlcube
 */
public class RangeMapping {
	/**
	 * @param n
	 *            value from range A
	 * @param ra1
	 *            range A, min value
	 * @param ra2
	 *            range A, max value
	 * @param rb1
	 *            range B, min value
	 * @param rb2
	 *            range B, max value
	 * @return value of n mapped into range B
	 * @since 04/07/2013
	 * @author dvlcube
	 */
	public static double linearTransform(double n, double ra1, double ra2, double rb1, double rb2) {
		return (n - ra1) / (ra2 - ra1) * (rb2 - rb1) + rb1;
	}

	public static double d(String v) {
		return Double.valueOf(v);
	}

	public static void main(String[] args) {
		double n = d(args[0]);
		double ra1 = d(args[1]);
		double ra2 = d(args[2]);
		double rb1 = d(args[3]);
		double rb2 = d(args[4]);

		System.out.println(linearTransform(n, ra1, ra2, rb1, rb2));
	}
}