MATLAB: From three vectors obtain the complete Vector that has the largest element, than the other two.

MATLABmatricesmatrixmatrix arraymatrix manipulation

Hello Goodnight.

I have 3 vectors that will constantly be changing the value of their elements. But the vector with the element greater than the elements of the other two vectors will be chosen. For example, of these three vectors the vector C would be chosen, since it has as element 18 and is the largest of the elements of the three vectors. The complete vector C will be chosen

A = [12 3 4 5 6]; B = [3 15 7 6 4]; C = [9 1 18 2 7];

In another combination it could be vector A or B depends on the maximum value of its elements.

How do I select the complete vector that contains at least one greater element than the other two?

Greetings and thanks.

Best Answer

A=[12 3 4 5 6];
B=[ 3 15 7 6 4];
C=[ 9 1 18 2 7];
R = [A(:);B(:);C(:)];
n = numel(A);
ii = ceil((1:3*n)/n);
[~,i1] = max(R);
out = R(ii == ii(i1));

or just

R = [A(:),B(:),C(:)];
[~,ii] = max(max(R));
out = R(:,ii);

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There are a number of ways to do this. A fully vectorized way is with cumsum, but it has a lot of extra calculations so may not be best, especially since MATLAB loops are no longer slow.

A = [1, 2, 54, 4, 5, 6; ...
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Solution 2

Give the rows are all identical except for the third column, you can cheat a little bit. If we leave out the 3rd column, then we only need to sum the first row up to the max of b.

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x(b)

If the every element of b was greater than or equal to 3, we could do something like

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w = (b >= n);

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c(w) = b(w)-1;

and finally get the answer

x(c)+w.*A(:, 3)

Best Answer

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