from
Chebfun
by Chebfun Team Numerical computation with functions instead of numbers.
plusquasimatrix
function pass = plusquasimatrix
% This test checks that quasimatrices of different sizes cannot be added.
% Rodrigo Platte Jun 2009
f = chebfun('x');
pass = false;
try
g = [f 2*f]+f;
catch
pass = true;
end