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1234
1234
19:57
1 2 3
4 5 6
7 8 9

1 2 3 0
4 5 6 0
7 8 9 0
0 0 0 0
do you convert 3x3 mat to 4x4 mat like the above?
how do you convert
less than 5 characters ;)... just kidding
a ← m,(1↑⍴a)⍴⍳0 ⋄ b←1↑⍴(⍉a) ⋄ (⍉a),b⍴⍳0
this is why I have, but.. 
a←n←1↑⍴m ⋄ m1←⍉m,n⍴⍳0 ⋄ m1,(n+1)⍴⍳0
better one
not working actually
 
2 hours later…
LdBeth
LdBeth
22:35
@1234 easy, try this 0,⍨0⍪⍨a←3 3⍴⍳9

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