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From: daryl@zaphod.uchicago.edu (Daryl McLaurine)
Newsgroups: comp.lang.pascal
Subject: Re: Real LOGn functions in TP 5.5 needed
Message-ID: <1991Mar21.042630.6174@midway.uchicago.edu>
Date: 21 Mar 91 04:26:30 GMT
References: <1991Mar20.145939.83@gnv.ifas.ufl.edu> <1991Mar20.220800.24027@midway.uchicago.edu> <1991Mar21.122959.346@matai.vuw.ac.nz>
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Organization: Dept. of Mathematics, Univ. of Chicago
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In article <1991Mar21.122959.346@matai.vuw.ac.nz> forbesmc@matai.vuw.ac.nz writes:
>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.
>
>+------------------------------------------------------------------+
>| I'm a toxophilite,         | Murray Forbes,                      |
>| so what's your problem?    | Physics Department,                 |
>|----------------------------| Victoria University of Wellington,  |
>| standard disclaimer :      | New Zealand.                        |
>| all opinions here are mine | FORBESMC@MATAI.VUW.AC.NZ            |
>+------------------------------------------------------------------+
This is the function I have been using, but I am getting some unexpected 
results. (Perhaps I mis-remebered the formula?). Also, I am doing real-time
analysis, and I thought that TP used a table for LN(), and making 2 passes
to that function would be murder (Not using a '387...I know...I know...).
I want a foolproof LOGn function that is fast, compact, and isn't dependent
on the LN() function.
	-dm
   ^
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   V Daryl McLaurine,     Systems Consultant / Associate
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