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ischar(arg1 [, arg2, ...])

Keywords: macros, general, variables, character variables
ischar(arg) returns True if arg is a CHARACTER variable or quoted string
and False otherwise.  If arg is undefined, ischar() returns False.

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

The principal use of ischar() is in checking the arguments of a macro
for appropriateness.  See argvalue() for another way to check for the
properties of macro arguments.

  Cmd> ischar("hello",3,T) # returns vector(T,F,F).

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

Gary Oehlert 2003-01-15