NAME
    isnum - whether a value is a numeric value

SYNOPSIS
    isnum(x)

TYPES
    x		any, &any

    return	int

DESCRIPTION
    Determine if x is a numeric value.  This function will return 1 if x
    is a a numeric value, 0 otherwise.

EXAMPLE
    > print isnum(2.0), isnum(1), isnum("0")
    1 1 0

    > print isnum(2i), isnum(1e20), isnum(1/3)
    1 1 1

LIMITS
    none

LIBRARY
    none

SEE ALSO
    isassoc, isatty, isblk, isconfig, isdefined, iserror, iseven, isfile,
    ishash, isident, isint, islist, ismat, ismult, isnull, isobj,
    isobjtype, isodd, isprime, isrand, israndom, isreal, isrel,
    issimple, issq, isstr, istype