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From: greg@athena.cs.uga.edu (GOD (Albert Ross))
Newsgroups: comp.lang.pascal
Subject: Re: Real LOGn functions in TP 5.5 needed
Message-ID: <1991Mar22.051119.12581@athena.cs.uga.edu>
Date: 22 Mar 91 05:11:19 GMT
References: <1991Mar20.145939.83@gnv.ifas.ufl.edu> <1991Mar20.220800.24027@midway.uchicago.edu> <1991Mar21.122959.346@matai.vuw.ac.nz>
Organization: University of Georgia, Athens
Lines: 30

In article <1991Mar21.122959.346@matai.vuw.ac.nz> forbesmc@matai.vuw.ac.nz writes:
>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
>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.

Unless I misunderstood the question, the formula should read:

	LOGn(x) = LOG(x) / LOG(n)

	where the right hand side LOGs are base 10.
	(this formula usually spawns from an equation
	 similiar to y=2^x where x is your base.  Take 
	 base 10 of each side and solve.)

Hope this helps....

greg@athena.cs.uga.edu          ALBATROSS rules!        University of Georgia
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