DELVAR Procedure
Deletes variables and their symbols from $MAIN$, the main program level of PV‑WAVE.
Usage
DELVAR, var1, ... ,varn
Input Parameters
vari — One or more named variables to be deleted.
Keywords
All — If specified, deletes all variables and their symbols on main program level.
Discussion
DELVAR may be called from any program level to delete a variable from the main program level. If DELVAR is called from the main program level, the variable is directly deleted.
When DELVAR is used to delete a local variable, the variable is also deleted from the main program level. If DELVAR is called from a procedure, one of the two following requirements applies:
UPVAR must be used to bind the local variable on the procedure level to the variable on the main program level.The variable on the main program level must be passed as a parameter to the procedure or function from which DELVAR is called.Example
This example creates three variables of differing type and structure, then deletes them using DELVAR.
; Create a single-precision, floating-point vector.
a = FINDGEN(3)
; Create an anonymous structure.
b = {structb, field1:1.0, field2:[5, 6, 7], field3:'PV-WAVE'}; Create a longword scalar.
c = 6L
INFO, a, b, c
; PV-WAVE prints the following:
; A FLOAT = Array(3)
; B STRUCT = -> STRUCTB Array(1)
; C LONG = 6
; Delete variables a and c.
DELVAR, a, c
INFO, a, b, c
; PV-WAVE prints the following:
; A UNDEFINED = <Undefined>
; B STRUCT = -> STRUCTB Array(1)
; C UNDEFINED = <Undefined>
; Delete variable b.
DELVAR, b
INFO, a, b, c
; PV-WAVE prints the following:
; A UNDEFINED = <Undefined>
; B UNDEFINED = <Undefined>
; C UNDEFINED = <Undefined>
See Also
For more information on releasing memory to the operating system, see the PV‑WAVE Programmer’s Guide.
