How to convert mat file to numpy array

问题

I want to convert a mat file with size 600 by 600 to numpy array and I got this error "float() argument must be a string or a number, not 'dict'" I am wondering how can I fix it.

    import numpy as np
    import scipy.io as sio
    test = sio.loadmat('Y7.mat')
    data=np.zeros((600,600))
    data[:,:]=test

回答1:

In [240]: from scipy.io import loadmat                                                        

Using a test mat file that I have from past SO questions:

In [241]: loadmat('test.mat')                                                                 
Out[241]: 
{'__header__': b'MATLAB 5.0 MAT-file Platform: posix, Created on: Sat Mar 21 20:09:30 2020',
 '__version__': '1.0',
 '__globals__': [],
 'x': array([[ 0,  3,  6,  9],
        [ 1,  4,  7, 10],
        [ 2,  5,  8, 11]])}

loadmat has given me a dictionary (see the {}?). This happens to have one array, with key 'x'. So I just access it with standard dictionary indexing:

In [242]: _['x']                                                                              
Out[242]: 
array([[ 0,  3,  6,  9],
       [ 1,  4,  7, 10],
       [ 2,  5,  8, 11]])

x was a variable in the MATLAB session that saved this file.

I don't know anything about what's on your file. print(list(data.keys())) can be used to see those keys/variable names.

I tried to get you to look at the loadmat docs, and see that it:

Returns
    mat_dictdict
        dictionary with variable names as keys, and loaded matrices as values.

来源：https://stackoverflow.com/questions/62274746/how-to-convert-mat-file-to-numpy-array