How can i have the posterior minimum and position of that?

Hello, I have a problem, I have the maximum of a vector, and I have to obtain posterior minimum and the position of that, i have this code, and it's ok but in the cell number 41 the maximum is the last number of the matrix, so Seg_leng-posi_max is 0, and matlab say me that: Second argument must be a positive scalar integer.

I don't know what to do for that case.

for l=1:length(Rd)

for k=1:1:num_Seg

[maxim(l,k),posi_max(l,k)]=max(x{l,k});

[posi_min{l,k},column{l,k},cero{l,k}]=find(x{l,k}<0,Seg_leng-posi_max(l,k),'last');

end

end

Seg_leng is the length of mi cell, 200, posi_max, is the position where is my maximum.

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