import tables from Matlab struct to matrices in python

I want to import tables from a struct in matlab and to store them in python as matrices.

this is the python code I tried

import scipy.io
import numpy as np

# Load the .mat file
data = scipy.io.loadmat('file.mat')

# Access the struct within the loaded data
my_struct = data['structkey']

# Convert each table to a matrix
table1_matrix = my_struct['table1'][0, 0]['arr']
print(table1_matrix)

this is whatwas printed:

[array([[3707764736],

[ 2],

[ 1],

[ 1],

[ 1],

[ 1]], dtype=uint32)]

I can't understand what is printed and don't know what to do to get the table stored in the struct as matrice in python

Answer 1

[ProblemSolver]

You need to careful about the datatype that you are working with.

I assume you are working with uint32, which is an unsigned 32-bit integer. Therefore, you have convert the data structure of the table:

table1_matrix = np.array(my_struct['table1'][0, 0]['arr'], dtype=np.float64)

I hope this helps!

[Mayssa Chouat]

I receive this error message :

TypeError: only size-1 arrays can be converted to Python scalars

The above exception was the direct cause of the following exception:

Traceback (most recent call last):

File "/home/mayssa/Desktop/50_PINNs/PINNDev/project1.py", line 8, in <module>

table1_matrix = np.array(my_struct['temperature_rod'][0, 0]['arr'], dtype=np.float64)

ValueError: setting an array element with a sequence.

[ProblemSolver]

Could you provide the file.mat, so that I can view what is exact data type of the matlab file.

Plus, you can try 'flatten()' to convert the nested array into a 1-D array, and then use astype(np.datatype), where the datatype should be exactly be the same datatype of the matlab "mat" file.

You can try this way as well:

https://www.mathworks.com/matlabcentral/answers/329801-passing-from-python-to-matlab-a-cell-array-of-structures?s_tid=answers_rc1-1_p1_MLT

[Mayssa Chouat]

This is my .mat file and it only stores a 1*1 struct with 8 fields

[ProblemSolver]

Try using this then:

import scipy.io

data = scipy.io.loadmat('file.mat');

temperature1 = data['your_field_temperature'] % replace 'm' with the field name that you have such as temperature_r..., the complete name
. % create each variable name
. % another variable and so on

print(temperature1)

This is the output I get.