Ensuring python equivalence of matlab's `fread`

As the comments suggest, you need to use a file descriptor, which is what the Matlab code is doing:

import numpy as np

def fread(fid, nelements, dtype):
     if dtype is np.str:
         dt = np.uint8  # WARNING: assuming 8-bit ASCII for np.str!
     else:
         dt = dtype

     data_array = np.fromfile(fid, dt, nelements)
     data_array.shape = (nelements, 1)

     return data_array

fid = open('test.bin', 'rb');

print fread(fid, 2, np.int16)
print fread(fid, 32, np.str)
print fread(fid, 2, np.int16)

Reading & Writing data to a file in binary requires the reader and writer to agree on a specified format. As the commenters suggest, endianess may become an issue if you save the binary on one computer and try to read it on another. If the data is always written and read on the same CPU, then you won't run into the issue.

Output for the test.bin:

MATLAB Output             Python+Numpy Output
------------------------------------------------------
ans =                     

    32                    [[32]
     0                     [ 0]]

ans =                   

    35                    [[ 35]
    32                     [ 32]
    97                     [ 97]
   102                     [102]
    48                     [ 48]
    52                     [ 52]
    50                     [ 50]
    95                     [ 95]
    53                     [ 53]
    48                     [ 48]
   112                     [112]
   101                     [101]
   114                     [114]
    99                     [ 99]
    95                     [ 95]
   115                     [115]
   112                     [112]
    97                     [ 97]
   110                     [110]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]
    32                     [ 32]]

ans =

    32                     [[32]
     0                      [ 0]]