SISNAN(3f)

NAME
SISNAN - .TRUE

SYNOPSIS

LOGICAL FUNCTION
    SISNAN(SIN)

REAL
    SIN

PURPOSE
SISNAN returns .TRUE. if its argument is NaN, and .FALSE. otherwise. To be replaced by the Fortran 2003 intrinsic in the future.

ARGUMENTS

SIN      (input) REAL
    Input to test for NaN.