CLEAR  CLEAR Clear or Delete a Variable


Usage
 
 Clears a set of variables from the current context, or alternately, 
 delete all variables defined in the current context.  There are
 two formats for the function call.  The first is the explicit form
 in which a list of variables are provided:
 
    clear a1 a2 ...
 
 The variables can be persistent or global, and they will be deleted.
 The second form
 
    clear 'all'
 
 clears all variables from the current context.  With no arguments,
 clear defaults to clearing 'all'.
 