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Re: Adding double-float values together

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On 8/20/2013 2:53 PM, Julio Di Egidio wrote:
> "Jongware" <jongware@no-spam.plz> wrote in message 
> news:521347b8$0$15903$e4fe514c@news2.news.xs4all.nl...
>> On 20-Aug-13 10:55 AM, industrial_one@hotmail.com wrote:
> <snipped>
>
>>> Is there ever a case where it makes sense to use a float for an 
>>> integer?
>
> The size of the significand is 23 bits for single-precision (i.e. 
> 32-bit) floats and 53 bits for double-precision (i.e. 64-bit) floats: 
> when converting from an integer, the value gets rounded if it cannot 
> fit in the significand.
>
>> Maybe there is a chance that a number could overflow max integer 
>> value, for each of the single entries or for the total after 
>> addition. Using floats makes sure you can count up to 10^38, but at 
>> the cost of precision.
>
> It is very easy here to overflow a 32-bit integer, as that would be 
> just 2 GB.  But I don't see any point in using doubles either, 64-bit 
> integers would be ideal: simpler, much more performant, and, I'd 
> assume, virtually impossible to overflow.
>
> Julio
>
I've seen some programs over at PrimeGrid that would overflow them 
easily, when trying
to find prime number integers with at least a million digits.

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Thread

Adding double-float values together industrial_one@hotmail.com - 2013-08-14 09:40 -0700
  Re: Adding double-float values together Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-14 18:23 +0100
    Re: Adding double-float values together industrial_one@hotmail.com - 2013-08-14 10:35 -0700
      Re: Adding double-float values together Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-14 19:22 +0100
        Re: Adding double-float values together industrial_one@hotmail.com - 2013-08-14 12:20 -0700
          Re: Adding double-float values together Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-15 02:05 +0100
            Re: Adding double-float values together Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-15 02:36 +0100
            Re: Adding double-float values together industrial_one@hotmail.com - 2013-08-14 18:42 -0700
              Re: Adding double-float values together Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-15 03:04 +0100
                Re: Adding double-float values together industrial_one@hotmail.com - 2013-08-14 21:17 -0700
                Re: Adding double-float values together Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2013-08-15 08:39 -0700
                Re: Adding double-float values together Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-15 17:02 +0100
                Re: Adding double-float values together industrial_one@hotmail.com - 2013-08-16 02:25 -0700
                Re: Adding double-float values together Ben Bacarisse <ben.usenet@bsb.me.uk> - 2013-08-16 12:45 +0100
                Re: Adding double-float values together industrial_one@hotmail.com - 2013-08-20 01:55 -0700
                Re: Adding double-float values together Jongware <jongware@no-spam.plz> - 2013-08-20 12:40 +0200
                Re: Adding double-float values together "Julio Di Egidio" <julio@diegidio.name> - 2013-08-20 20:53 +0100
                Re: Adding double-float values together Robert Miles <milesrf@Usenet-News.net> - 2013-08-24 09:22 -0500
                Re: Adding double-float values together "Julio Di Egidio" <julio@diegidio.name> - 2013-08-24 15:49 +0100

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