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Re: What is the command to do a power of a value

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  To: Roedy Green
From: Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at>

On Sun, 29 Jul 2012 21:28:11 -0700 (PDT), xvictoryeohx@gmail.com wrote:
> C=L(1+i/100)power of n

 x ^ n  =  exp ( log(x) * n )    |  x = (1 + i/100)
        = exp ( log( 1 + i/100 ) * n)
        = exp ( log1p ( i/100 ) * n)

If you're doing more calculations with same interest-rate but different 
periods, then you may want to calculate
  double logBase = Math.log1p( i / 100 );
once, and use that for the individual calculations:
  C = L * Math.exp( logBase * n )

The gist of this response is, that for the kind of base (1+i/100), you better 
separate the pow operation out into log and exp, and actually use log1p on 
(i/100) instead of log on (1+i/100) for efficiency's and precision's sake.

For "Math.log1p" see:
http://docs.oracle.com/javase/6/docs/api/java/lang/Math.html#log1p%28double%29

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What is the command to do a power of a value "xvictoryeohx" <xvictoryeohx@1:261/38.remove-rf4-this> - 2012-07-30 19:00 +0000
  Re: What is the command to do a power of a value "bugbear" <bugbear@1:261/38.remove-rf4-this> - 2012-07-30 19:00 +0000
  Re: What is the command to do a power of a value "glen herrmannsfeldt" <glen.herrmannsfeldt@1:261/38.remove-rf4-this> - 2012-07-30 19:00 +0000
    Re: What is the command to do a power of a value "xvictoryeohx" <xvictoryeohx@1:261/38.remove-rf4-this> - 2012-07-30 19:00 +0000
  Re: What is the command to do a power of a value "Roedy Green" <roedy.green@1:261/38.remove-rf4-this> - 2012-07-30 19:00 +0000
    Re: What is the command to do a power of a value "Andreas Leitgeb" <andreas.leitgeb@1:261/38.remove-rf4-this> - 2012-07-30 19:00 +0000
      Re: What is the command to do a power of a value "Patricia Shanahan" <patricia.shanahan@1:261/38.remove-rf4-this> - 2012-07-30 19:00 +0000
        Re: What is the command to do a power of a value Patricia Shanahan <pats@acm.org> - 2012-07-30 13:15 -0700
        Re: What is the command to do a power of a value glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-07-30 22:26 +0000
          Re: What is the command to do a power of a value Patricia Shanahan <pats@acm.org> - 2012-07-30 16:01 -0700
          Re: What is the command to do a power of a value Andreas Leitgeb <avl@gamma.logic.tuwien.ac.at> - 2012-07-30 23:11 +0000
        Re: What is the command to do a power of a value "Andreas Leitgeb" <andreas.leitgeb@1:261/38.remove-dpk-this> - 2012-07-31 18:02 +0000

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