{{{mat}}} files contain data saved in Matlab's proprietary format. How to read these files in Python depends on the version of Matlab used to save them, up to 7.1 or greater.

Here are exemples of how to read two variables {{{lat}}} and {{{lon}}} from a mat file called "test.mat".

= Matlab up to 7.1 =
mat files created with Matlab up to version 7.1 can be read using the {{{mio}}} module part of {{{scipy.io}}}. Reading structures (and arrays of structures) is supported, elements are accessed with the same syntax as in Matlab: after reading a structure called e.g. {{{struct}}}, its {{{lat}}} element can be obtained with {{{struct.lat}}}, or {{{struct.__getattribute__('lat')}}} if the element name comes from a string.

{{{
#!python
#!/usr/bin/env python
from scipy.io import loadmat
x = loadmat('test.mat')
lon = x['lon']
lat = x['lat']
# one-liner to read a single variable
lon = loadmat('test.mat')['lon']
}}}
= Matlab 7.3 and greater =
Beginning at release 7.3 of Matlab, mat files are actually saved using the HDF5 format by default (except if you use the -vX flag at save time, see {{{help save}}} in Matlab). These files can be read in Python using, for instance, the [http://www.pytables.org/moin PyTables] or [http://h5py.alfven.org/ h5py] package. Reading Matlab structures in mat files does not seem supported at this point.

{{{
#!python
#!/usr/bin/env python
import tables
file = tables.openFile('test.mat')
lon = file.root.lon[:]
lat = file.root.lat[:]
# Alternate syntax if the variable name is in a string
varname = 'lon'
lon = file.getNode('/' + varname)[:]
}}}