Getting undefined variable with if exist

Question

I assume this is a trivial mistake on my part but it is driving me nuts.

???Undefined function or variable "antenna_02".

Error in ==>test_model at 6
if exist(antenna_02.mat, 'file')

I know it isn't defined that is why I am using if exist. Any help would be gladly appreciated and may just save my sanity.

Answer 1

You need to enclose "antenna_02.mat" in apostrophes (''):

if exist('antenna_02.mat', 'file')

Otherwise MATLAB tries to interpret it as a structure variable and complains that there's no variable called antenna_02.