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Re: Log base 2 of large integers

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Date Wed, 13 Aug 2014 08:16:40 -0500
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Subject Re: Log base 2 of large integers
From Skip Montanaro <skip@pobox.com>
To Mok-Kong Shen <mok-kong.shen@t-online.de>
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On Wed, Aug 13, 2014 at 8:05 AM, Mok-Kong Shen
<mok-kong.shen@t-online.de> wrote:
> I like to compute log base 2 of a fairly large integer n but
> with math.log(n,2) I got:
>
> OverflowError: long int too large to convert to float.
>
> Is there any feasible work-around for that?

A bit of googling turned up this page:

http://gnumbers.blogspot.com/2011/10/logarithm-of-large-number-it-is-not.html

Might be worth studying for ideas.

Skip

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Thread

Log base 2 of large integers Mok-Kong Shen <mok-kong.shen@t-online.de> - 2014-08-13 15:05 +0200
  Re: Log base 2 of large integers Skip Montanaro <skip@pobox.com> - 2014-08-13 08:16 -0500
    Re: Log base 2 of large integers Mok-Kong Shen <mok-kong.shen@t-online.de> - 2014-08-13 15:50 +0200
  Re: Log base 2 of large integers Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-08-13 23:32 +1000
    Re: Log base 2 of large integers Mok-Kong Shen <mok-kong.shen@t-online.de> - 2014-08-13 15:46 +0200
      Re: Log base 2 of large integers Marko Rauhamaa <marko@pacujo.net> - 2014-08-13 17:00 +0300
      Re: Log base 2 of large integers Andrew Jaffe <a.h.jaffe@gmail.com> - 2014-08-13 15:06 +0100
    Re: Log base 2 of large integers Peter Otten <__peter__@web.de> - 2014-08-13 16:17 +0200
  Re: Log base 2 of large integers Peter Otten <__peter__@web.de> - 2014-08-13 15:58 +0200
    Re: Log base 2 of large integers Peter Pearson <ppearson@nowhere.invalid> - 2014-08-13 16:12 +0000
      Re: Log base 2 of large integers Marko Rauhamaa <marko@pacujo.net> - 2014-08-13 19:15 +0300
      Re: Log base 2 of large integers Chris Angelico <rosuav@gmail.com> - 2014-08-14 02:18 +1000
      Re: Log base 2 of large integers Ian Kelly <ian.g.kelly@gmail.com> - 2014-08-13 12:13 -0600
  Re:Log base 2 of large integers Dave Angel <davea@davea.name> - 2014-08-13 10:10 -0400

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