Source code for irfpy.moon.anomaly

''' Magnetic anomaly model.

Purucker's model is implemented in :class:`AnomalyModelPME`.
'''
import os
import warnings
import numpy as np
from pkg_resources import resource_filename

from irfpy.util import irfpyrc

class AnomalyModelPME:
    ''' Purucker's Model.

    Refer to M. E. Purucker 2010 in JGR planets.
    http://core2.gsfc.nasa.gov/research/purucker/moon_2010/

    >>> am = AnomalyModelPME()
    >>> print(am.br.shape)
    (361, 361)
    >>> print(am.lonlist[0:3])
    [0. 1. 2.]
    >>> print(am.latlist[0:3])
    [90.  89.5 89. ]
    >>> print(am.lonlist[130])
    130.0
    >>> print(am.latlist[75])
    52.5
    >>> print(am.br[130, 75])
    0.69
    >>> print(am.bt[130, 75])
    -0.53
    >>> print(am.bp[130, 75])
    -0.49


    .. todo::

        Better user interface. Probably by giving longitude and
        latitude, user may get a vector.
    '''

    def __init__(self):
        ''' Load a data file.

        The data is obtained from
        http://core2.gsfc.nasa.gov/research/purucker/moon_2010/

        The corrective model with file name
        ``brtps_d1_170_alt30_har14tol15_dip6cpadpr_phase30_correlation.xy``
        is supported here.  Download it, and place it to your prefered folder
        and specify by .irfpyrc, which should be [moon] section purucker_anomaly_data entry.
        '''

        warnings.warn("The data is based on Purucker's publication and "
            "provision via the Internet.  I would appreciate it. "
            "Users should refer to the web page and the publication in "
            "http://core2.gsfc.nasa.gov/research/purucker/moon_2010/ "
            "for details of the data.")
        
#        self.fnam = resource_filename(__name__, os.path.join('datafile',
#            'brtps_d1_170_alt30_har14tol15_dip6cpadpr_phase30_correlation.xy'))

        rc = irfpyrc.Rc()
        self.fnam = rc.get('moon', 'purucker_anomaly_data')

        # Data is every 0.5 degrees for lat 1.0 for lon.
        nlon = 361
        nlat = 361
        
        datall = np.genfromtxt(self.fnam)

        self.lon = datall[:, 0].reshape([361, 361]).T
        self.lat = datall[:, 1].reshape([361, 361]).T

        self.br = datall[:, 2].reshape([361, 361]).T
        self.bt = datall[:, 3].reshape([361, 361]).T
        self.bp = datall[:, 4].reshape([361, 361]).T
        self.b = datall[:, 5].reshape([361, 361]).T

        self.lonlist = self.lon[:, 0].copy()
        self.latlist = self.lat[0, :].copy()

import unittest
import doctest


def doctests():
    return unittest.TestSuite((
        doctest.DocTestSuite(),
        ))
if __name__ == '__main__':
    unittest.main(defaultTest='doctests')