** About **
This program contains two Python modules: igrf and cxform.

Module igrf provides several useful methods based on IGRF v.10.
The wrapper has been written by David Parunakian, Skobeltsyn Institute of Nuclear Physics of the Moscow State University.
Feel free to contact me with improvement suggestions, questions etc at either rumith@srd.sinp.msu.ru or dp@xientific.info.
The model itself is the result of hard work of many people from different institutions, such as IAGA and NASA.
The source code and coefficient files used can be found at ftp://nssdcftp.gsfc.nasa.gov/models/geomagnetic/igrf/fortran_code/
More information on IGRF can be found here: http://www.ngdc.noaa.gov/IAGA/vmod/igrf.html

Module cxform provides access to one function - transform(), which can be used for transforming cartesian coordinates
from one coordinate system to another. Complete documentation on cxform, as well as the list of coordinate systems supported,
can be found at CXFORM official website http://nssdcftp.gsfc.nasa.gov/selected_software/coordinate_transform/


** Installation **
tar -xzf igrf.tar.gz
cd igrf
./install.sh

The above procedure will install coefficient files to /usr/local/lib/igrf. If you wish to install them to another directory (e.g. /var/foobar), run
./install.sh /var/foobar
instead. PLEASE ONLY SPECIFY ABSOLUTE PATHS.

** Usage **
To use igrf in your software after you have installed it, include the following line in your code:

import igrf

After that, you can use the following functions:

igrf.dimo(year): 
	Find the geomagnetic dipole moment in Gauss (normalized to the Earth's radius) at the specified time (decimal year)

igrf.lb(lat, lon, alt, year):
	Find the L-shell and geomagnetic field intensity (l, b tuple) at the specified latitude, longitude, altitude and decimal year

igrf.b(lat, lon, alt, year):
	Find the Earth's magnetic field value (Bnorth, Beast, Bdown, Babs tuple) using the spherical harmonics model

igrf.b0(lat, lon, alt, year, stps):
	Find the smallest magnetic field strength on a field line. Stps is step size for field line tracing

Latitude and longitude should be specified in the geographic coordinate system.
Altitude should be specified in kilometers above sea level.
Decimal year is a float and looks like 2003.45.


** Legal **
This project is distributed under the terms of the GNU General Public License v.3. The full text of the license is available
in the LICENSE file.