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Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？

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Am 08.10.2012 16:07, schrieb iMath:
> To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？

Algorithms are generally language-agnostic, so what is your question

> BTW ，Windows’s calculator get the accurate value ，anyone who knows how to implement it ?

You should use a library that handles arbitrary-precision floating point 
numbers, Python's built-in floating point type corresponds to C's double 
type and that is typically a IEEE float, which means a limited 
precision. Just search the web for one. If you really want to do it 
yourself, you could leverage the fact that Python's integral type has a 
dynamic size, so that it can represent numbers with more than the 
typical 32 or 64 bits width.

BTW: If this is not a homework question, you should ask much more 
specifically. My anwers are intentionally vague in order to not spoil 
you the learning effect.

Cheers!

Uli

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To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？ iMath <redstone-cold@163.com> - 2012-10-08 07:07 -0700
  Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？ Dave Angel <d@davea.name> - 2012-10-08 10:48 -0400
  Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？ Chris Angelico <rosuav@gmail.com> - 2012-10-09 02:00 +1100
    Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm � Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-10-09 11:39 +0000
  Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？ Dave Angel <d@davea.name> - 2012-10-08 11:13 -0400
  Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？ Ulrich Eckhardt <ulrich.eckhardt@dominolaser.com> - 2012-10-08 16:44 +0200
  Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？ Chris Angelico <rosuav@gmail.com> - 2012-10-09 02:19 +1100
  Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？ Terry Reedy <tjreedy@udel.edu> - 2012-10-08 21:45 -0400
  Re: To get the accurate value of 1 - 0.999999999999999 ,how to implement the python algorithm ？ Dave Angel <d@davea.name> - 2012-10-08 22:20 -0400

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