Undefined function 'variable' for input arguments of type char

1

when I run my cvx code on Linux system, it display this error :undefined function ‘variable’ for input arguments of type char
But on Windows system it does not display error.

% Objective update
cvx_begin quiet
variable Z(4,K) nonnegative
…
cvx_end

Any idea of why does this happen?

2

Try reinstalling CVX, and note whether there are any warnings or errors. If you are using CVX 3.0beta, switch to CVX 2.1. Beyond that, I have no idea.