Matlab sparse matrix does not come out as I would expect

This is my code:
S=sparse([1 3 2 1 4],[3 1 4 1 4],[1 2 3 4 5],4,4)
full(s)
However, when I run it, I get:
'S =
(1,1) 4
(3,1) 2
(1,3) 1
(2,4) 3
(4,4) 5
ans=
0 0 0 1
0 1 0 0
1 2 0 0
0 0 3 0'
Please tell me why ans is not [4 0 1 0;0 0 0 3; 2 0 0 0; 0 0 0 5]?

 Accepted Answer

S=sparse([1 3 2 1 4],[3 1 4 1 4],[1 2 3 4 5],4,4)
S = 4x4 sparse double matrix (5 nonzeros)
(1,1) 4 (3,1) 2 (1,3) 1 (2,4) 3 (4,4) 5
full(S)
ans = 4×4
4 0 1 0 0 0 0 3 2 0 0 0 0 0 0 5
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It works just fine.
What did you do wrong? LOOK CAREFULLY AT WHAT YOU WROTE. MATLAB is case sensitive in variable names.
You created the matrix S. Then you looked at full(s). Should MATLAB know that you wanted to see what was in the variable S, and not in the variable s? The mind reading toolbox never works correctly. ;-)

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Asked:

on 3 Feb 2025

Commented:

on 3 Feb 2025

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