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isdefined()

Usage:
isdefined(arg1 [, arg2, ...])



Keywords: macros, general, variables
isdefined(arg) returns True if arg exists in the MacAnova workspace and
False otherwise.  If arg is a built-in function, isdefined() returns
True.

isdefined(arg1, arg2, ..., argk) returns a LOGICAL vector, each element
of which is True or False depending on whether or not the corresponding
argument actually exists.

In a macro, isdefined() is useful for checking errors in a macro.  For
instance, a macro to compute mean square errors might have the line
 if(!isdefined(SS) || !isdefined(DF)){
    error("SS or DF not defined")}
before attempting to use SS or DF.

See topics 'macros', isarray(), ischar(), isfactor(), isfunction(),
isgraph(), islogic(), ismacro(), ismatrix(), isname(), isnull(),
isnumber(), isreal(), isscalar(), isstruc(), isvector().


Gary Oehlert 2003-01-15