Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!elroy.jpl.nasa.gov!decwrl!waikato.ac.nz!comp.vuw.ac.nz!matai.vuw.ac.nz!forbesmc
From: forbesmc@matai.vuw.ac.nz
Newsgroups: comp.lang.pascal
Subject: Re: Real LOGn functions in TP 5.5 needed
Message-ID: <1991Mar21.122959.346@matai.vuw.ac.nz>
Date: 21 Mar 91 00:29:59 GMT
References: <1991Mar20.161211.28435@javelin.es.com> <1991Mar20.145939.83@gnv.ifas.ufl.edu> <1991Mar20.220800.24027@midway.uchicago.edu>
Organization: Victoria University of Wellington,  NZ
Lines: 24

In article <1991Mar20.220800.24027@midway.uchicago.edu>, news@midway.uchicago.edu (News Administrator) writes:
> A quick question...
> 	TP has a natural log function.  I need a LOGn(x) function that
> does not need a table lookup, and is highly accurate.  Is there a quick 
> algorithm or a real math library avalable?
> 	-dm
> From: daryl@zaphod.uchicago.edu (Daryl McLaurine)
> Path: zaphod!daryl
> 
Look up the required function in any standard maths book or 'log tables' -
I think it goes something like this ;

       LOGn(x) = LN(x) / LN(n)

where LN is the natural log function and n is the log base required,
x is the number whose log you require.

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| I'm a toxophilite,         | Murray Forbes,                      |
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| all opinions here are mine | FORBESMC@MATAI.VUW.AC.NZ            |
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