DELVAR procedure deletes
variables from the main IDL program level. DELVAR frees any memory used by the variable and removes it from the main program's symbol table. The following restrictions apply:
DELVAR can only be called from the main program level.
Each time DELVAR is called, the main program is erased. Variables that are not deleted remain unchanged.
, ..., V
One or more named variables to be deleted.
Suppose that the variable Q is defined at the main program level. Q can be deleted by entering: