A3. Real arithmetic

Functions
Function	D1num (I As Long, Optional Info As Long) As Double
	IEEE 754 special numbers (double precision)
Function	IsFinite (X As Double) As Boolean
	Determine if finite value
Function	IsInf (X As Double) As Boolean
	Determine if infinite value
Function	IsNan (X As Double) As Boolean
	Determine if NaN (Not-a-Number) value
Function	IsNormal (X As Double) As Boolean
	Determine if normal number
Function	Signbit (X As Double) As Boolean
	Determine sign of number
Sub	D1num_sub (Ret As Double, I As Long, Optional Info As Long)
	IEEE 754 special numbers (double precision) (Subroutine version)
Sub	IsFinite_sub (Ret As Boolean, X As Double)
	Determine if finite value (Subroutine version)
Sub	IsInf_sub (Ret As Boolean, X As Double)
	Determine if infinite value (Subroutine version)
Sub	IsNan_sub (Ret As Boolean, X As Double)
	Determine if NaN (Not-a-Number) value (Subroutine version)
Sub	IsNormal_sub (Ret As Boolean, X As Double)
	Determine if normal number (Subroutine version)
Sub	Signbit_sub (Ret As Boolean, X As Double)
	Determine sign of number (Subroutine version)

Detailed Description

This is the group of A3. Real arithmetic routines.