ISSET ISSET Test If Variable Set

Usage

Tests for the existence and non-emptiness of a variable.
the general syntax for its use is

   y = isset('name')

where name is the name of the variable to test.  This
is functionally equivalent to 

   y = exist('name','var') & ~isempty(name)

It returns a logical 1 if the variable is defined 
in the current workspace, and is not empty, and returns
a 0 otherwise.