sun_position.py 文件源码

def hour_angle(hUTC, dayofyear, year, longitude):
    """ Sun hour angle

    Args:
        hUTC: fractional hour (UTC time)
        dayofyear (int):
        year (int):
        longitude (float): the location longitude (degrees, east positive)


    Returns:
        (float) the hour angle (hour)

    Details:
        World Meteorological Organization (2006).Guide to meteorological
        instruments and methods of observation. Geneva, Switzerland.
    """
    jd = julian_date(hUTC, dayofyear, year)
    n = jd - 2451545
    gmst = numpy.mod(6.697375 + 0.0657098242 * n + hUTC, 24)
    lmst = numpy.mod(gmst + longitude / 15., 24)
    ra = right_ascension(hUTC, dayofyear, year)
    ha = numpy.mod(lmst - ra / 15. + 12, 24) - 12
    return ha