time_utils.py 文件源码

def convert_gps_time(gpsweek, gpsweekseconds, format='unix'):
    """
    convert_gps_time :: (String -> String) -> Float

    Converts a GPS time format (weeks + seconds since 6 Jan 1980) to a UNIX timestamp
    (seconds since 1 Jan 1970) without correcting for UTC leap seconds.

    Static values gps_delta and gpsweek_cf are defined by the below functions (optimization)
    gps_delta is the time difference (in seconds) between UNIX time and GPS time.
    gps_delta = (dt.datetime(1980, 1, 6) - dt.datetime(1970, 1, 1)).total_seconds()

    gpsweek_cf is the coefficient to convert weeks to seconds
    gpsweek_cf = 7 * 24 * 60 * 60  # 604800

    :param gpsweek: Number of weeks since beginning of GPS time (1980-01-06 00:00:00)
    :param gpsweekseconds: Number of seconds since the GPS week parameter
    :return: (float) unix timestamp (number of seconds since 1970-01-01 00:00:00)
    """
    # GPS time begins 1980 Jan 6 00:00, UNIX time begins 1970 Jan 1 00:00
    gps_delta = 315964800.0
    gpsweek_cf = 604800

    if isinstance(gpsweek, pd.Series) and isinstance(gpsweekseconds, pd.Series):
        gps_ticks = (gpsweek.astype('float64') * gpsweek_cf) + gpsweekseconds.astype('float64')
    else:
        gps_ticks = (float(gpsweek) * gpsweek_cf) + float(gpsweekseconds)

    timestamp = gps_delta + gps_ticks

    if format == 'unix':
        return timestamp
    elif format == 'datetime':
        return datetime.datetime(1970, 1, 1) + pd.to_timedelta(timestamp, unit='s')