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Hi to all, In the code below I take a picture and convert it into a 3d array numpy (cordinates x, y of each pixel and color rgb) Then skim this array and sequentially extract of the matrices 5 x 5 x 3 (then arrays of 5 x 5 px most the rgb values 3) and insert them in an array

from PIL import Image  
import numpy as np  

img = Image.open("img.jpg")  
arr = np.array(img)  

x = []  
h,w,rgb = arr.shape  
size = 5  

for i in range(0,h):  
    for j in range(0,w):  
        part = arr[i:i+size,j:j+size]  
        if len(part)==size and len(part[0])==size:  
            x.append(part)

The result is something like:

...  
[[129, 166, 175],  
[129, 166, 175],  
[130, 167, 175],  
[128, 166, 175],  
[128, 166, 175]],  

...  

[[129, 166, 174],  
[129, 166, 174],  
[129, 166, 175],  
[129, 166, 175],  
[128, 166, 175]]], dtype=uint8), 129, 166, 175, array([[[129, 166, 175],  
[128, 166, 175],  
[128, 166, 175],  
[128, 166, 175],  
[128, 168, 176]],  

...  

[[129, 166, 174],  
[129, 166, 175],  
[129, 166, 175],  
[128, 166, 175],  
[129, 167, 176]]], dtype=uint8), 129, 166, 175, array([[[128, 166, 175],  
[128, 166, 175],  
[128, 166, 175],  
[128, 168, 176],  
[128, 168, 178]],  

...  

[[129, 166, 175],  
[129, 166, 175],  
[128, 166, 175],  
[129, 167, 176],  
[128, 168, 176]]], dtype=uint8), 128, 166, 175]

While I would expect something like

...  
[[129, 166, 175],  
[129, 166, 175],  
[130, 167, 175],  
[128, 166, 175],  
[128, 166, 175]],  

...  

[[129, 166, 174],  
[129, 166, 174],  
[129, 166, 175],  
[129, 166, 175],  
[128, 166, 175]]], dtype=uint8), array([[[129, 166, 175],  
[128, 166, 175],  
[128, 166, 175],  
[128, 166, 175],  
[128, 168, 176]],  

...  

[[129, 166, 174],  
[129, 166, 175],  
[129, 166, 175],  
[128, 166, 175],  
[129, 167, 176]]], dtype=uint8), array([[[128, 166, 175],  
[128, 166, 175],  
[128, 166, 175],  
[128, 168, 176],  
[128, 168, 178]],  

...  

[[129, 166, 175],  
[129, 166, 175],  
[128, 166, 175],  
[129, 167, 176],  
[128, 168, 176]]], dtype=uint8)]

So a matrix that is always 5 x 5 x 3 not in some one-dimensional points after the fact ", dtype=uint8)," I would expect a, array([[[128, 166, 175], and not a 128, 166, 175
thank you.
```

@iacoposk8 This would be a good use of pdb, since you could look at what you are appending each cycle in the loop. Or, just print out something in each loop such as part.shape. I wonder if this isn't just a display issue (things getting overwritten or omitted?)... have you actually checked the type/sizes of the elements in x?