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Subject: Re: [geometry] Negative distance?
From: Volker Schöch (vschoech_at_[hidden])
Date: 2012-04-16 04:37:20

Hi Barend,

any news on this issue? Do you have any idea when 1.50 might be ready? 1.48 to 1.49 was only three months, but I cannot seem to find any hints on a 1.50 roadmap on the website.


Volker Schöch | vschoech_at_[hidden]
Senior Software Engineer
think-cell Software GmbH | Chausseestr. 8/E | 10115 Berlin | Germany | phone +49 30 666473-10 | US phone +1 800 891 8091
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-----Original Message-----
From: geometry-bounces_at_[hidden] [mailto:geometry-bounces_at_[hidden]] On Behalf Of Barend Gehrels
Sent: Monday, March 19, 2012 10:12 PM
To: Boost.Geometry library mailing list
Subject: Re: [geometry] Negative distance?
Hi Volker,
On 19-3-2012 11:44, Volker Schöch wrote:
> Hi Barend,
>> Thanks for your report. However, I cannot reproduce it.
>> [...] Attached my program to verify this.
> I tried your reproduction. It's alright except that your points are based on double. Change that template paramter T of template<typename T>  void test_distance() to int and you'll see what I see. It is actually worse (well, different at least) than I thought: The result is not negative, it is "not a number". NaN lets my check for negative results fail, so I prematurely assumed the result was a negative distance. I apologize.
Ah. Indeed I get -nan for int, using 1.48. Sorry for not-testing int, at that moment did not think that you're using int's.
Actually I cannot explain why this specificly fails with int and succeeds with double. I'm a bit surprised by it but have currently no time to research it further, and besides that it is fixed in the Trunk version.
So yes, it is fixed in Trunk but alas not yet for 1.49 (the current release). If that is the case I probably know what is the case (but still don't know why it is only on int) and I can tell how to patch it. 
If it is possible for you to patch 1.48 or 1.49 I'll tell you. Otherwise you have to wait for 1.50. Sorry for the error.
Regards, Barend

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