Xref: utzoo misc.wanted:4058 comp.lang.c:16568
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From: tcamp@dukeac.UUCP (Ted A. Campbell)
Newsgroups: misc.wanted,comp.lang.c,triangle.general,micro.general,triangle.graphics,micro.ibm
Subject: Wanted: fast, low-precision trig functions for C
Message-ID: <1256@dukeac.UUCP>
Date: 27 Feb 89 17:41:57 GMT
Organization: Academic Computing, Duke University, Durham, NC
Lines: 18


I am writing a graphics-based program that has to calculate 
several thousand map coordinates.  The slowest part of this 
program by far is its trigonometric functions--it takes 
3 minutes and 45 seconds to calculate 3000 sets ofd coordinates
on an XT clone at 10 mhz (no coprocessor), which is the lowest 
resolution map I can make.  

I wondered if there were any fast, low-precision approaches 
to the standard trig functions, since the compilers I use
(Microsoft QuickC and AT&T Unix C) boast of their high 
level of precision?  

Any suggestions will be appreciated.  Thanks.  

Ted A. Campbell
Duke Divinity School 
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