How do I check if all numbers in a vector are the same?

I have a row vector A. I'd like to verify whether all numbers in this vector are the same. How can I do this?

Thanks!

Answer 1

[Stephen23]

all(diff(A)==0)
min(A)==max(A) % does not work for NaN
range(A)==0 % RANGE requires the statistics toolbox
numel(unique(A))==1

[Robert Brown]

Stephen actually gave not only 1 but what appears to be 3 solutions to the problem ! very good ! (overachiever !)

I don't seem to have range(A). Is that in a newer version of MATLAB? or is it in a toolbox?