CLEAR	Clear various quantities from the workspace.
 	CLEAR removes all variables from the workspace.
 	CLEAR VARIABLES does the same thing.
 	CLEAR X removes variable or function X from the workspace.
 	CLEAR FUNCTIONS removes all compiled M-functions.
 	CLEAR MEX removes all links to MEX-files.
 	CLEAR ALL removes all variables, functions and MEX links.
 
 	If X is global, CLEAR X removes X from the current workspace,
 	but leaves it accessible to any functions declaring it global.
 	CLEAR GLOBAL X completely removes the global variable X.
 	CLEAR GLOBAL removes all global variables.