# min function on two arrays

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Robert Demyanovich on 8 Jun 2021
Commented: Walter Roberson on 8 Jun 2021
I've read the documentation on the min function, but still don't understand how it works on two arrays. I have the following:
dS=zeros(1,N)
dS=min(cA(i+1,:),cB(i+1,:))
where cA and cB are equally sized arrays. Doesn't the min function just take the value at equivalent locations in cA or cB that is the lowest. So if position 10,50 in cA is 5 and the same position in cB is 3, min returns 3 in the resulting row vector, dS, at column 50. Is that correct?
James Tursa on 8 Jun 2021
This line creates dS as a vector:
dS=zeros(1,N)
Then this line completely overwrites the dS you just created and instead assigns dS the result of the min( ) function call:
dS=min(cA(i+1,:),cB(i+1,:))
I.e., the first line is completely useless and accomplishes nothing because it gets overwritten in the second line.
And yes, cA(i:1,:) and cB(i+1,:) will be a row vectors if i is a scalar.

SALAH ALRABEEI on 8 Jun 2021
%
dS=min([cA(i+1,:),cB(i+1,:)])
Walter Roberson on 8 Jun 2021
That would work in the case that cA and cB have the same number of columns.
The original code
dS=min(cA(i+1,:),cB(i+1,:))
would also work if one of cA or cB had a single column and the other one did not.