# argmax of vector in matlab

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Mohamed Jamal on 20 May 2020
Answered: Raunak Gupta on 28 May 2020
Hi guys, Im searching if there's argmax in matlab for this term W*V , argmax(W*V) related to W (v is constant and W is variable so argmax is related to W) .. W and V are vectors ... any help how can I find the maximum vector of W that maximaize the term W*V ? thanks alot !!!!
James Tursa on 20 May 2020
This is not clear. If V and W are both vectors, what do you intend the operation W*V to produce? Is this supposed to be an inner product or outer product? What are the sizes of V and W?

Raunak Gupta on 28 May 2020
Hi,
From the question I understand you have a vector V that is constant, and you are taking dot product with a vector W, assuming both have same length. This operation of finding maximum value of that term cannot be called as argmax instead it’s looks as an optimization problem where you need to maximize W.*V given V and there is no constraint on W.
Since, you didn’t mention any constraint on values inside W, logically I can say that maximum can be infinity by setting W accordingly. For these maximization problems ideally, you need constraint on vector that needs to be calculated.
You can setup the optimization problem as mentioned here using fmincon. Since you want to maximize the value you can put a negative on full objective function because fmincon minimizes the objective function by default.
Hope it helps!