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Re: Adding double-float values together

From "Julio Di Egidio" <julio@diegidio.name>
Newsgroups comp.programming
Subject Re: Adding double-float values together
Date 2013-08-20 20:53 +0100
Organization A noiseless patient Spider
Message-ID <kv0hgd$13v$1@dont-email.me> (permalink)
References (9 earlier) <0.593019630819eda7e2dd.20130815170222BST.87zjsjgcxe.fsf@bsb.me.uk> <6918786f-e5f4-4306-80dc-a6ca6518f14d@googlegroups.com> <0.496dbdcba00648308483.20130816124501BST.87ioz5272a.fsf@bsb.me.uk> <23ce3ae2-c11c-41a5-be47-bce7e3928480@googlegroups.com> <521347b8$0$15903$e4fe514c@news2.news.xs4all.nl>

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"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

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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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