Re: big numbers

From: Axel Naumann <Axel.Naumann_at_cern.ch>
Date: Mon, 11 Jun 2007 15:46:49 +0200


Hi,

This is fixed in CINT; the patch will arrive shortly in ROOT. Thanks for reporting!

Cheers, Axel.

Nevzat Guler wrote:

> 	Hello,
> 	Related to my previous question: I found that conversion from
> unsigned long long to double does not work properly. But when I use long
> double everything is ok.
> So, I think my problem is solved by using long double instead of double.
> 	Best regards,
> 
> 				Nevzat Guler
> 
> On Sun, 10 Jun 2007, Roland Kuhn wrote:
> 

>> Hi Nevzat!
>>
>> On 10 Jun 2007, at 14:46, Nevzat Guler wrote:
>>
>>> Hello,
>>> I am trying to divide following some big numbers, Below is the
>>> simplified version of what I am doing with actual numbers:
>>> long long int a = 6488530998;
>>> long long int b = 7409765618;
>>> double c = ((double)(a)) / ((double)(b));
>>> I print out the numbers but c comes out to be c = 1.7806
>>>
>> There's something funny going on:
>>
>> root [1] long long int a = 6000000000LL
>> [...]
>> root [11] a/1
>> (long long)6000000000
>> root [12] a/2
>> (long long)3000000000
>> root [13] a/2.
>> (double)5.00000000000000000e-01
>> root [14] cout << (double)a << endl
>> 1
>>
>> So, you've probably forgotten the LL suffix (I'm on MacOS X and got
>> an error when I tried that), but even with that the conversion from
>> long long to double does not work... BTW:
>>
>> root [18] a=12000000000LL
>> (const long long)12000000000
>> root [19] cout << (double)a << endl
>> 2
>>
>> Funny, isn't it?
>>
>> Ciao,
>> Roland
>>
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>>

>
> Received on Mon Jun 11 2007 - 15:46:55 CEST

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