How to find the index of the center element in a 2d array if all the elements are the same?

I'm attempting to find the index of the center element to be used later on.

I have a 5x5 array of -1's created with the following code.

x = -1*ones(5,5)

I'm able to find the index of the center element if the center element differs from the other elements using find (x == value).

Answer 1

[Star Strider]

If all the elements are the same, one approach is:

x = -1*ones(5,5);
[r,c] = ind2sub(size(x), ceil(numel(x)/2))

Thsi will only work on matrices with odd numbers of elements.

[Tim]

Thanks for the response. That wasn't exactly what I was looking for but your response helped me arrive at what I was looking for. The approach I used to find the linear index is:

x = -1*ones(5,5);
indx = sub2ind(size(x),ceil(length(x)/2),ceil(length(x)/2))

indx =

    13

[Star Strider]

As always, my pleasure!

The linear index is actually just:

indx = ceil(numel(x)/2);

I wasn’t certain which one you wanted, so I opted for the subscripts as the desired result.