How do read .npy files in matlab?

Hello.

In matlab it is possible to read the extension .npy, or in its absence the extension .LVM of Labview.

[Stephen23]

"In matlab it is possible to read the extension .npy..."

https://www.mathworks.com/matlabcentral/answers/444998-how-do-read-npy-files-in-matlab#answer_1348042

Answer 1

[Andrew Knyazev]

https://github.com/kwikteam/npy-matlab

[Maria Magnusson]

I copied readNPY.m and readNPYheader.m from there and could then easily read npy-images into matlab.

Thankyou very much! /Maria

[Carlos Theran Suarez]

Excellent!! Thankyou very much...

[Cinar Gulleroglu]

Is it possible for you to show or briefly explain how to use this readNPY.m and readNPYheader.m/how to integrate this to our codes?

[Maria Jose Palancares Sosa]

Super useful, thanks!

[Svetlana Piner]

Best response from my point of view!

Answer 2

[Toon Weyens]

If you have access to Python, the easiest thing would be to create a Python script such as the one below, and run that. It will find all .npz files in the current directory and convert that to .mat.

from scipy.io import savemat
import numpy as np
import glob
import os

npzFiles = glob.glob("*.npz")
for f in npzFiles:
    fm = os.path.splitext(f)[0]+'.mat'
    d = np.load(f)
    savemat(fm, d)
    print('generated ', fm, 'from', f)

[Sandra Chimeumanu Meshack]

i tried this, it seems to work but it's asking me to allow_pickle=True

[Leonardo da Silva Costa]

In my case I had to do something like this

X = np.load('./dataset/dataset_Xs.npy')

savemat('./dataset/dataset_Xs.mat', {'X': X})

[Varun Vasudevan]

This works. Thanks Leonardo :)

[Grzegorz Klosowski]

Good job. Thanks.

[Mark Sie]

Help me greatly thank u

[Mehrdad]

thank you

[Stephen23]

"the easiest thing would be to create a Python script such as the one below, and run that."

This is easier:

https://www.mathworks.com/matlabcentral/answers/444998-how-do-read-npy-files-in-matlab#answer_1348042

Answer 3

[Grace Kepler]

Yes, use code like this.

x = py.numpy.load('data.npy')

[Mike Jonson]

No. That'd be how to do it with python, not in MATLAB.

[MathWorks Supported Compilers Team]

Hi Mike,

Did you try it? This works for me. Note that "py." is prepended to the normal Python command "numpy.load('data.npy')".

>> x=py.numpy.load('data.npy')

x =

Python ndarray:

1 2 3

4 5 6

7 8 9

[Stephen23]

"No. That'd be how to do it with python, not in MATLAB."

No, that is how to do it from MATLAB, not from Python:

https://www.mathworks.com/help/matlab/call-python-libraries.html

https://www.mathworks.com/help/matlab/matlab_external/create-object-from-python-class.html

Answer 4

[Cam Salzberger]

Hello Juan,

I don't believe that either of those file formats are natively supported in MATLAB, but you can always check File Exchange to see if anyone has written an importer for them. A quick search did not turn up anything for NPY, but LVM turned up this one. If you have any questions about that File Exchange package, it's best to direct them to the author of the package.

-Cam

[Johann Martinez]

One more reason to stop using Matlab. Python indeed has libraries to make use Matlab.

[Stephen23]

"Python indeed has libraries to make use Matlab."

MATLAB indeed has functions to make use Python:

https://www.mathworks.com/help/matlab/matlab_external/ways-to-call-python-from-matlab.html

https://www.mathworks.com/help/matlab/matlab_external/create-object-from-python-class.html