What does
cvx_version
show?
If it is CVX 3.0beta, follow the advice at CVX 3.0beta is riddled with bugs, which are very unlikely to ever be fixed. Use the latest build of CVX 2.2
If you are already running CVX 2.2, try reinstalling CVX in a fresh MATLAB session.
If that doesn’t work, what is the output from
which -all cellfun
Maybe there you have another `cellfun which is being called which is incompatible with what CVX expects.