# NAG Library Routine Document

## 1Purpose

x02amf returns the safe range of floating-point arithmetic.

## 2Specification

Fortran Interface
 Function x02amf ( )
 Real (Kind=nag_wp) :: x02amf
#include nagmk26.h
 double x02amf_ ()

## 3Description

x02amf is defined to be the smallest positive model number $z$ such that for any $x$ in the range [$z,1/z$] the following can be computed without undue loss of accuracy, overflow, underflow or other error:
• $-x$
• $1/x$
• $-1/x$
• $\sqrt{x}$
• $\mathrm{log}\left(x\right)$
• $\mathrm{exp}\left(\mathrm{log}\left(x\right)\right)$
• ${y}^{\left(\mathrm{log}\left(x\right)/\mathrm{log}\left(y\right)\right)}$ for any $y$

None.

None.

None.

None.

## 8Parallelism and Performance

x02amf is not threaded in any implementation.