?laisnan

Tests input for NaN.

Syntax

val = slaisnan( sin1, sin2 )

val = dlaisnan( din1, din2 )

Include Files

mkl.fi

Description

This logical routine checks for NaNs (NaN stands for 'Not A Number') by comparing its two arguments for inequality. NaN is the only floating-point value where NaN ≠ NaN returns .TRUE. To check for NaNs, pass the same variable as both arguments.

This routine is not for general use. It exists solely to avoid over-optimization in ?isnan.

Input Parameters

sin1, sin2

REAL for sisnan

Two numbers to compare for inequality.

din2, din2

DOUBLE PRECISION for disnan

Two numbers to compare for inequality.

Output Parameters

val: Logical. Result of the comparison.