How to load cell array of strings in Matlab mat files into Python list or tuple using Scipy.io.loadmat

Question

I am a Matlab user new to Python. I would like to write a cell array of strings in Matlab to a Mat file, and load this Mat file using Python (maybe scipy.io.loadmat) into some similar type (e.g list of strings or tuple of strings). But loadmat read things into array and I am not sure how to convert it into a list. I tried the "tolist" function which does not work as I expected ( I have a poor understanding of Python array or numpy array). For example:

Matlab code:

cell_of_strings = {'thank',  'you', 'very', 'much'};
save('my.mat', 'cell_of_strings');

Python code:

matdata=loadmat('my.mat', chars_as_strings=1, matlab_compatible=1);
array_of_strings = matdata['cell_of_strings']

Then, the variable array_of_strings is:

array([[[[u't' u'h' u'a' u'n' u'k']], [[u'y' u'o' u'u']],
    [[u'v' u'e' u'r' u'y']], [[u'm' u'u' u'c' u'h']]]], dtype=object)

I am not sure how to convert this array_of_strings into a Python list or tuple so that it looks like

list_of_strings = ['thank',  'you', 'very', 'much'];

I am not familiar with the array object in Python or numpy. Your help will be highly appreciated.

Answer 1

Have your tried this:

import scipy.io as si

a = si.loadmat('my.mat')
b = a['cell_of_strings']                # type(b) <type 'numpy.ndarray'>
list_of_strings  = b.tolist()           # type(list_of_strings ) <type 'list'>

print list_of_strings 
# output: [u'thank', u'you', u'very', u'much']