Document: WG14 N1246


Trig function cleanup


Submitter: Fred Tydeman (USA)
Submission Date: 2007-07-26
Source: WG14
Version: 1.0
Date: 2007-07-26
Subject: Unclear range of trig math functions

Problem

Section 7.12.4 Trigonometric functions is unclear in the Returns section if the pi is mathematical or a machine representation, and is unclear if the functions are allowed or prohibited from returning a floating-point value exceeding the specified range.

Suggested change for C1x

Add a paragraph to section 7.12.4 along the lines of:

The Returns sections are in terms of ideal mathematical functions and mathematical pi. But, due to, one or more of, machine representations of floating-point numbers, rounding, and implementation algorithms, the actual returned value may exceed the listed range.