“Converting” Numpy arrays to Matlab and vice versa

Question

I am looking for a way to pass NumPy arrays to Matlab.

I\'ve managed to do this by storing the array into an image using scipy.misc.imsave and then loa

Answer 1

Not sure if it counts as "simpler" but I found a solution to move data from a numpy arrray created in a python script which is called by matlab quite fast:

dump_reader.py (python source):

import numpy

def matlab_test2():
    np_a    = numpy.random.uniform(low = 0.0, high = 30000.0, size = (1000,1000))
    return np_a

dump_read.m (matlab script):

clear classes
mod = py.importlib.import_module('dump_reader');
py.importlib.reload(mod);

if count(py.sys.path,'') == 0
    insert(py.sys.path,int32(0),'');
end

tic
A = py.dump_reader.matlab_test2();
toc
shape = cellfun(@int64,cell(A.shape));
ls = py.array.array('d',A.flatten('F').tolist());
p = double(ls);
toc
C = reshape(p,shape);
toc

It relies on the fact that matlabs double seems be working efficiently on arrays compared to cells/matrices. Second trick is to pass the data to matlabs double in an efficient way (via pythons native array.array).

P.S. sorry for necroposting but I struggled a lot with its and this topic was one of the closest hits. Maybe it helps someone to shorten the time of struggling.

P.P.S. tested with Matlab R2016b + python 3.5.4 (64bit)