From: Todd Benson <caduceass@...>
Date: 2008-09-15T00:40:05+09:00
Subject: Re: how do deal with huge numbers and keep them accurate?

On Sun, Sep 14, 2008 at 7:18 AM, Tomi Zzzz <tomi_z@nana.co.il> wrote:
> Hello all, I wrote the following code:
>
> require "bigdecimal"
> require "bigdecimal/math"
> include BigMath
> odd = gets.chomp.to_f
> result = odd/3.0
> puts result.to_f
> blank = gets.chomp
>
> the code works just fine when the input is upto 15 digits, but
> afterwards the code fails to give the correct output.
>
> a few good examples:
> odd=1231231
> result=410410.333333333
>
> odd=123123123123121    (15 digits)
> result=41041041041040.3
>
> so far so good,now:
> odd=1231231231231231   (16 digits)
> result=4.1041041041041e+014     (given with no remainder)
>   [It's a wrong answer! the result should have been  ---
> 410410410410410.33333]
>
> What do i need to chance in the code to make it happen?
> in the future i should deal with larger numbers and the accuracy is
> essential.
>
> thanks in advanced, tomi.

require 'bigdecimal'
require 'bigdecimal/math'
include BigMath
a = BigDecimal('1231231231231231')
b = 3.0
puts a/b
b = BigDecimal('3')
puts a/b

Todd