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isreal()

Usage:

isreal(arg1 [, arg2, ...] [,positive:T or negative:T or nonneg:T]\
  [,integer:T])

Keywords: macros, general, variables

isreal(arg) returns True if arg is a REAL variable and False otherwise.
If arg is undefined, isreal() returns False.

isreal(arg, integer:T) does the same, except that True is returned only
if arg is REAL and all the values are integers.

isreal(arg, positive:T), isreal(arg, negative:T) and isreal(arg,
nonneg:T) do the same, except that True is returned only if arg is REAL
and all its elements have the indicated properties.  You can use
'integer:T' here as well.

isreal(arg1, arg2, ..., argk [keywords]) returns a LOGICAL vector, each
element of which is True or False depending on whether or not the
corresponding argument is REAL and satisfies the properties specified by
any keywords.

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

Example:
  Cmd> isreal("hello",3,T)  # returns vector(F,T,F).

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