International Geomagnetic Reference Field IGRF12 and IGRF11...in simple, object-oriented Python ≥ 3.6 or Matlab ≥ R2014b.

A Fortran compiler is required, such as gfortran:

• Linux: apt install gfortran
• Mac: brew install gcc
• gfortran for Windows (MinGW)

To get the IGRF12 development version, git clone and then:

python -m pip install -e .

Otherwise, for the latest release from PyPi:

python -m pip install igrf12

Optionally, test the install with:

pytest

If you get ImportError on Windows for the Fortran module, try from the iri2016 directory:

del *.pyd
python setup.py build_ext --inplace --compiler=mingw32

To make the plots in this readme:

igrf12

using as a Python module at geodetic coordinates 65N, 148W:

import igrf12

mag = igrf12.igrf('2010-07-12', glat=65, glon=-148, alt_km=100)

returns an xarray.Dataset:

<xarray.Dataset>
Dimensions:  (alt_km: 1)
Coordinates:
  * alt_km   (alt_km) int64 100
Data variables:
    north    (alt_km) float64 1.122e+04
    east     (alt_km) float64 4.148e+03
    down     (alt_km) float64 5.302e+04
    total    (alt_km) float64 5.436e+04
    incl     (alt_km) float64 77.29
    decl     (alt_km) float64 20.29

The IGRF model may be specified with the igrf12.igrf(model=) option:

• 11: IGRF11
• 12: IGRF12

Matlab ≥ R2014b can seamlessly call Python modules, as in igrf12.m. Instead of the $1000 Aerospace Toolbox, use this free IGRF12 for Matlab.

If you only want the plain Fortran program, you can do:

cd bin

cmake ../src
cmake --build .

./testigrf

• IGRF12 Fortran code
• IGRF11 Fortran code
• WMM2015 inclination map
• WMM2015 declination map