public double Dtf2d(int ihour, int imin, double sec) throws palError {
        /* Preset status */
        Status = 0;

        TRACE("Dtf2d");
        /* Validate sec, min, hour */
        ENDTRACE("Dtf2d");
        if ((sec < 0.0) || (sec >= 60.0)) {
            Status = 1;
            throw new palError(1, "Dtf2d: sec outside range 0-59.999...");
        }
        if ((imin < 0) || (imin > 59)) {
            Status = 2;
            throw new palError(1, "Dtf2d: min outside range 0-59");
        }
        if ((ihour < 0) || (ihour > 23)) {
            Status = 1;
            throw new palError(1, "Dtf2d: hour outside range 0-23");
        }

        /* Compute interval */
        return (60.0 * (60.0 * ihour + imin) + sec) / D2S;
    }