private static int getDMSSecFrac(final int degE6) {
        final long rounded = roundToPrecision(degE6, 3600000L);
        return (int) (rounded % 1000L);
    }
Get the fractional part of the longitude seconds scaled up by 1000 (DMS format).
main/src/main/java/cgeo/geocaching/location/Geopoint.java