# For loop help!

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BiaoZhun on 18 Nov 2020
Answered: Stephen Cobeldick on 18 Nov 2020
I need helpt with a for loop to pick numbers from a vector and put them in an existing non square in the order shown in the figure below (hop it makes sense). It starts at the dot and then follow the arrow. the resulting matrix should be as the one in the blackbackgrownd figure.
Sorry if this has been asked before <3 .
Thank you.

BiaoZhun on 18 Nov 2020
The indexing patter should be as the same way as in the figure with the arrows, for which I hope the figure makes sense.
James Tursa on 18 Nov 2020
BiaoZhun on 18 Nov 2020
yes, but it has to start one after the other, starts with 3(lets say n) and increments by 3's and then goes through the whole vector and then starts 2(n-1) an incremebts by 3's then goes through the whole vector agian, and then starts at 1(n-2) and increments by 3's. Hope this makes a better idea of the problem.

Stephen Cobeldick on 18 Nov 2020
"... so becase of the amount of data i need a for loop"
I doubt that using a loop would be a good approach.
V = 1:12;
R = 3;
M = flipud(reshape(V,R,[]))
M = 3×4
3 6 9 12 2 5 8 11 1 4 7 10
V = rand(118668,1);
R = 9889;
M = flipud(reshape(V,R,[]));
size(M)
ans = 1×2
9889 12