Java Double Number mod mod2pi(double vin)

Description

Ensure that v is [-PI, PI]

License

Open Source License

Declaration

static public double mod2pi(double vin) 

Method Source Code

//package com.java2s;

public class Main {
    static double twopi_inv = 0.5 / Math.PI;
    static double twopi = 2.0 * Math.PI;

    /** Ensure that v is [-PI, PI] **/
    static public double mod2pi(double vin) {
        double v;

        if (vin < 0)
            v = -mod2pi_pos(-vin);//ww w  .j a v  a2  s .  c om
        else
            v = mod2pi_pos(vin);

        // Validation test:
        //   if (v < -Math.PI || v > Math.PI)
        //      System.out.printf("%10.3f -> %10.3f\n", vin, v);

        return v;
    }

    /** Returns a value of v wrapped such that ref and v differ by no
     * more +/-PI
     **/
    static public double mod2pi(double ref, double v) {
        return ref + mod2pi(v - ref);
    }

    static private double mod2pi_pos(double vin) {
        double q = vin * twopi_inv + 0.5;
        int qi = (int) q;

        return vin - qi * twopi;
    }
}

Related

1. mod(double x, double m)
2. mod(double x, double y)
3. mod(double x, double y)
4. mod(double x, double y)
5. mod(final double a, final double b)
6. mod2pi_pos(double vin)
7. modArray(double value, int mod, int div)
8. modifiedGramSchmidt(double[][] s)
9. modifiedJulianToJulian(double modifiedJulian)