How to check if all the numbers in a column of a matrix are equal and return that value

I am trying to construct a way to find a column of equal numbers in matrix of any size. There will only be one column where the numbers are equal. I then need to extract that number (the number that is the same throughout the column) to a variable that can be called on. I have tried for loops, but I cannot get it to work. Any help would be greatly appreciated.

Answer 1

[Azzi Abdelmalek]

If A is your matrix

idx=find(all(~diff(A)))
out=A(1,idx)

[William]

Thanks!