Finding the matrix with the most elements?

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Hello all,
I'm kinda new to matlab so I'm still trying find my way through the way things work. That said I have a question that I need some help on:
I have 3 matrix arrays of varying sizes, called say V1, V2, and V3. How would I go about programming the code so that matlab finds the matrix with the most elements.
I want to save the number of elements in the largest matrix as it's own variable, "LarMat", and I know how to do that already, it's just that finding the largest of the three is giving me some trouble.
  1 Comment
Azzi Abdelmalek
Azzi Abdelmalek on 7 Jan 2015
V1=[1 2;3 4]
V2=[0 1 2;3 4 1]
V3=[5 6 0 1;2 3 0 1;1 1 0 1]
What would be the result?

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Accepted Answer

Star Strider
Star Strider on 7 Jan 2015
This is one way:
V1 = rand(2,2);
V2 = rand(3,3);
V3 = rand(4,4);
[els,idx] = max([numel(V1) numel(V2) numel(V3)]);
The ‘els’ variable will tell you the maximum number of elements, and the ‘idx’ variable will tell you which one. (It is ‘V3’ — the third matrix whose elements are determined — here.)
  3 Comments
Star Strider
Star Strider on 7 Jan 2015
My pleasure!
Thank you for the compliment.
Image Analyst
Image Analyst on 7 Jan 2015
Andrew, what was the method you were using to find "LarMat"?

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More Answers (2)

Image Analyst
Image Analyst on 7 Jan 2015
Try this:
% Check the number of elements against LarMat,
% which you say that you've computed already (or at least know how to).
if LarMat == numel(V1)
fprintf('V1 is the largest.\n');
elseif LarMat == numel(V2)
fprintf('V2 is the largest.\n');
else
fprintf('V3 is the largest.\n');
end

Chad Greene
Chad Greene on 7 Jan 2015
V1 = rand(1,5);
V2 = rand(4,3);
V3 = magic(2);
% Number of elements in each matrix:
numels = [numel(V1) numel(V2) numel(V3)];
% Max number of elements per matrix:
LarMat = max(numels)
% Matrix with most elements:
BiggestMatrix = find(numels==LarMat)

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