How to reshape a 3D array to 2D array along the diagonals?

I have the following matrices:

X= 1 2 3       
   4 5 6
   7 8 9

Y= 3 4 7
   2 4 6
   1 2 5

I wish to reshape the matrix as

 Z= 1 2 3 0 0 0
    4 5 6 0 0 0
    7 8 9 0 0 0
    0 0 0 3 4 7
    0 0 0 2 4 6
    0 0 0 1 2 3

How can this be achieved?

Answer 1

[Ahmet Cecen]

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