aacgmv2.wrapper.convert_latlon_arr()

Complexity

Conditions

26

Size

Total Lines	135
Code Lines	68

Duplication

Lines	0
Ratio	0 %

Importance

Changes

0

# -*- coding: utf-8 -*-
def convert_latlon_arr(in_lat, in_lon, height, dtime, code="G2A"):
    """Converts between geomagnetic coordinates and AACGM coordinates.  At least
    one of in_lat, in_lon, and height must be a list or array

    Parameters
    ------------
    in_lat : (np.ndarray or list or float)
        Input latitude in degrees N (code specifies type of latitude)
    in_lon : (np.ndarray or list or float)
        Input longitude in degrees E (code specifies type of longitude)
    height : (np.ndarray or list or float)
        Altitude above the surface of the earth in km
    dtime : (datetime)
        Single datetime object for magnetic field
    code : (int or str)
        Bit code or string denoting which type(s) of conversion to perform
        G2A        - geographic (geodetic) to AACGM-v2
        A2G        - AACGM-v2 to geographic (geodetic)
        TRACE      - use field-line tracing, not coefficients
        ALLOWTRACE - use trace only above 2000 km
        BADIDEA    - use coefficients above 2000 km
        GEOCENTRIC - assume inputs are geocentric w/ RE=6371.2
        (default = "G2A")

    Returns
    -------
    out_lat : (np.ndarray)
        Output latitudes in degrees N
    out_lon : (np.ndarray)
        Output longitudes in degrees E
    out_r : (np.ndarray)
        Geocentric radial distance (R_Earth) or altitude above the surface of
        the Earth (km)
    """
    import aacgmv2._aacgmv2 as c_aacgmv2

Unable to import 'aacgmv2._aacgmv2'

    # If a list was entered instead of a numpy array, recast it here
    if isinstance(in_lat, list):
        in_lat = np.array(in_lat)

    if isinstance(in_lon, list):
        in_lon = np.array(in_lon)

    if isinstance(height, list):
        height = np.array(height)

    # If one or two of these elements is a float or int, create an array
    test_array = np.array([hasattr(in_lat, "shape"), hasattr(in_lon, "shape"),
                           hasattr(height, "shape")])
    if not test_array.all():
        if test_array.any():
            arr_shape = in_lat.shape if test_array.argmax() == 0 else \
                        (in_lon.shape if test_array.argmax() == 1 else
                         height.shape)
            if not test_array[0]:
                in_lat = np.ones(shape=arr_shape, dtype=float) * in_lat
            if not test_array[1]:
                in_lon = np.ones(shape=arr_shape, dtype=float) * in_lon
            if not test_array[2]:
                height = np.ones(shape=arr_shape, dtype=float) * height
        else:
            logging.info("for a single location, consider using convert_latlon")
            in_lat = np.array([in_lat])
            in_lon = np.array([in_lon])
            height = np.array([height])

    # Ensure that lat, lon, and height are the same length or if the lengths
    # differ that the different ones contain only a single value
    if not (in_lat.shape == in_lon.shape and in_lat.shape == height.shape):
        ulen = np.unique([in_lat.shape, in_lon.shape, height.shape])
        if ulen.min() != (1,):
            logging.error("mismatched input arrays")
            return None, None, None

    # Test time
    if isinstance(dtime, dt.date):
        dtime = dt.datetime.combine(dtime, dt.time(0))

    assert isinstance(dtime, dt.datetime), \
        logging.error('time must be specified as datetime object')

    # Test height
    if np.min(height) < 0:
        logging.warn('conversion not intended for altitudes < 0 km')

    # Initialise output
    lat_out = np.empty(shape=in_lat.shape, dtype=float) * np.nan
    lon_out = np.empty(shape=in_lon.shape, dtype=float) * np.nan
    r_out = np.empty(shape=height.shape, dtype=float) * np.nan

    # Test code
    try:
        code = code.upper()

        if(np.nanmax(height) > 2000 and code.find("TRACE") < 0 and
           code.find("ALLOWTRACE") < 0 and code.find("BADIDEA")):
            estr = 'coefficients are not valid for altitudes above 2000 km. You'
            estr += ' must either use field-line tracing (trace=True '
            estr += 'or allowtrace=True) or indicate you know this '
            estr += 'is a bad idea'
            logging.error(estr)
            return lat_out, lon_out, r_out

        # make flag
        bit_code = convert_str_to_bit(code)
    except AttributeError:
        bit_code = code

    assert isinstance(bit_code, int), \
        logging.error("unknown code {:}".format(bit_code))

    # Test latitude range
    if np.abs(in_lat).max() > 90.0:
        assert np.abs(in_lat).max() <= 90.1, \
            logging.error('unrealistic latitude')
        in_lat = np.clip(in_lat, -90.0, 90.0)

    # Constrain longitudes between -180 and 180
    in_lon = ((in_lon + 180.0) % 360.0) - 180.0

    # Set current date and time
    c_aacgmv2.set_datetime(dtime.year, dtime.month, dtime.day, dtime.hour,
                           dtime.minute, dtime.second)

    # Vectorise the AACGM code
    convert_vectorised = np.vectorize(c_aacgmv2.convert)

    # convert
    try:
        lat_out, lon_out, r_out = convert_vectorised(in_lat, in_lon, height,
                                                     bit_code)
    except:

General except handlers without types should be used sparingly.

        pass

    return lat_out, lon_out, r_out