Why does the EXIST function return an incorrect value in stand-alone mode?

Question

MathWorks Support Team 2009-6-27

Whenever I try to use the EXIST function in standalone mode, the wrong results are returned.

For instance the following code returns 0 in stand-alone mode:

function redbatmod
eat = 1;
exist('eat')
exist('flames')

Answer 1

The EXIST function has limitations for support in stand-alone mode. For more information, see the solution attached at the bottom of this page.

As a workaround, you can use either NARGIN or the following code, if you wish to check for the existence of a variable:

function texist2
nw = 2;
try
      isempty(nw);
      myexist=1;
catch
      myexist=0;
end
fprintf(1,'exist: %d\n',myexist);