undef

Syntax

undef(obj, [objType=VAR])

or

undef all

Arguments

obj a string or a string vector indicating the names of objects to be undefined. To undefine all the variables in a category, use the unquoted “all” for obj.

objType type of objects to be undefined. The types can be: VAR (variable), SHARED (shared variable) or DEF (function definition). The default value is VAR.

To delete all user-defined objects in the system except shared variables, use “undef all”.

Details

Release variables or function definitions from the memory. You can also release a local variable (VAR) from the memory using “= NULL”.

Examples

$ undef all;
$ x=1
$ undef(`x);
$ x=1
$ y=2
$ undef(`x`y);
$ share table(1..3 as x, 4..6 as y) as t
$ undef(`t, SHARED);
$ def f(a){return a+1}
$ undef(`f, DEF);
$ a=1
$ b=2
$ undef all, VAR;