Overview

This is a Python wrapper for the Apex fortran library by Emmert et al. [2010] [1], which allows converting between geodetic, modified apex, and quasi-dipole coordinates as well as getting modified apex and quasi-dipole base vectors (Richmond [1995] [2]). The geodetic system used here is WGS84. MLT calculations are also included. The package is free software (MIT license).

Quick start

Install from PyPI using pip:

pip install apexpy

This assumes that the same version of libgfortran is installed in the same location as when the pip wheel was built (if a wheel was used). If not, you may have trouble importing apexpy. If you run into trouble, try the command:

pip install --no-binary :apexpy: apexpy

which requires both libgfortran and gfortran to be installed on your system.

Conversion is done by creating an Apex object and using its methods to perform the desired calculations. Some simple examples:

>>> from apexpy import Apex
>>> from __future__ import print_function
>>> A = Apex(date=2015.3)  # datetime objects are also supported
>>> # geo to apex, scalar input
>>> mlat, mlon = A.convert(60, 15, 'geo', 'apex', height=300)
>>> print("{:.12f}, {:.12f}".format(mlat, mlon))
57.477310180664, 93.590156555176
>>> # apex to geo, array input
>>> glat, glon = A.convert([90, -90], 0, 'apex', 'geo', height=0)
>>> print(["{:.12f}, {:.12f}".format(ll, glon[i]) for i,ll in enumerate(glat)])
['83.103820800781, -84.526657104492', '-74.388252258301, 125.736274719238']
>>> # geo to MLT
>>> import datetime as dt
>>> mlat, mlt = A.convert(60, 15, 'geo', 'mlt', datetime=dt.datetime(2015, 2, 10, 18, 0, 0))
>>> print("{:.12f}, {:.12f}".format(mlat, mlt))
56.598316192627, 19.107861709595
>>> # can also convert magnetic longitude to mlt
>>> mlt = A.mlon2mlt(120, dt.datetime(2015, 2, 10, 18, 0, 0))
>>> print("{:.2f}".format(mlt))
20.90

If you don't know or use Python, you can also use the command line. See details in the full documentation.

Documentation

https://apexpy.readthedocs.org/

References

Badges

docs
tests
package