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Loading matlab binary (.mat) files into python

It happens. You have old data in matlab .mat format or your colleagues insist, for some obscure reason, on using MATLAB. You need scipy.io.loadmat and scipy.io.savemat from scipy.

import scipy.io
X = scipy.io.loadmat('mydata.mat')

X now contains a dictionary whose keys correspond to the variable names saved in the original mat file.

UPDATE:
Nested dictionaries seem to be a problem. A kind soul has a short set of methods that converts nested dictionaries here.

UPDATE:

Look here (scipy cookbook) for how to handle mat files from recent versions of matlab
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Comments

  1. CamillaJune 12, 2009 at 3:51 AM

    Hi,
    Loved this trick:)

    ReplyDelete
  2. AnonymousOctober 31, 2009 at 9:53 PM

    thanks! it's very useful

    ReplyDelete
  3. AnonymousJanuary 10, 2010 at 2:52 AM

    Very useful, thanks

    ReplyDelete
  4. AnonymousJuly 23, 2010 at 1:43 PM

    Doesn't read Matlab 7.3 files. It complains and suggests using the HDF reader.

    ReplyDelete
  5. Kaushik GhoseJuly 26, 2010 at 8:28 AM

    Hi,

    Thanks for pointing that out! From the cookbook (http://www.scipy.org/Cookbook/Reading_mat_files) I see that they suggest using PyTables or h5py packages.

    ReplyDelete
  6. NicolauAugust 8, 2010 at 12:48 PM

    Thank you so much! I love to find out something like that is actually extremely easy. :)

    ReplyDelete

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