CGAL users discussion list

[Juan Carlos Lopez Alfonso <>]

Hi Andreas:

Thank you again for your answer and your help. I have a question: Are
you running this example in a Release mode?  About that I could have
something wrong, I dont know what is it,  because I am running exactly
this example. In all cases I have a correct triangulation, but with 3
hours of computing approximately.

best regards
Juan Carlos

On Tue, Oct 25, 2011 at 9:40 PM, Andreas Fabri
<>
 wrote:
> Hi Juan Carlos,
>
> On my Intel Core 2 duo 2.8 Ghz   your program takes 37 min.
> And I bring it down to 5 min with our local fix.
>
> If it takes hours on your machine you probably do something
> wrong.
>
> best regards,
>
> andreas
>
> On 25/10/2011 15:15, Juan Carlos Lopez Alfonso wrote:
>>
>> Hi:
>>
>> Thank again for your help. In these links you can download  the
>> example code (example.cpp) and the data file (either in .rar or .txt),
>> with the set of points, where in the first line of this file is the
>> number of points and in the other lines the listed set of points. If
>> you didn't download these files, please tell me where I can put them
>> in order that you can prove my example and give me any suggestion.
>>
>> http://dl.dropbox.com/u/2516160/example.cpp
>> http://dl.dropbox.com/u/2516160/treatmentPoints.rar
>> http://dl.dropbox.com/u/2516160/treatmentPoints.txt
>>
>> In my case, I am sure that I have several group of points with the
>> same x,y and only varying the z (you can see my file of points and is
>> very easy see that), because I am trying to triangulate a TAC of a
>> radiotherapy patient with the defined organs involved. I have for all
>> slices of a TAC diferent points with the same value of x,y only
>> varying the coordinate z. I am using a set of points of a radiotherapy
>> treatment plan and from different slice of the TAC in 2D I am forming
>> a 3D domain with these points. For this reason, I have almost the same
>> points x,y only varying the z for each slice of the TAC.
>>
>> Best Regards from madrid and waiting for your answer
>> Juan Carlos
>>
>> On Tue, Oct 25, 2011 at 2:23 PM, Andreas Fabri
>> <>
>>   wrote:
>>>
>>> If you want you can post your code,
>>> and put the data on a server so that we can
>>> download it and try to reproduce/fix the problem.
>>>
>>> It might also be the data. We had a user where
>>> all points where on a 3D grid, or all points
>>> where organized in k groups with identical x,y
>>> and only varying z coordinate, where CGAL was
>>> rather slow. We have a not yet released solution
>>> for that.
>>>
>>> best regards,
>>>
>>> andreas
>>>
>>> On 25/10/2011 14:14, Juan Carlos Lopez Alfonso wrote:
>>>>
>>>> Hi:
>>>>
>>>> Thank you again for your answer. Yes, you are right I am using
>>>> Exact_predicates_inexact_constructions_kernel. For example with 4618
>>>> points, when I use the Triangulation_3 the triangulation is computed
>>>> in 3 sec and with Delaunay_triangulation_3 in 20 sec.
>>>>
>>>> But my real simulation is with more than 3500 000 of points and 3.5
>>>> hours is much time for my time real simulations only computing the
>>>> triangulation.
>>>>
>>>> Any comment about how I can do to improve my simulation time?
>>>>
>>>> Best regards agian, and sorry for your time
>>>> Juan Carlos
>>>>
>>>> On Tue, Oct 25, 2011 at 1:49 PM, Marc 
>>>> Glisse<>
>>>>  wrote:
>>>>>
>>>>> On Tue, 25 Oct 2011, Juan Carlos Lopez Alfonso wrote:
>>>>>
>>>>>> Thank you for your answer. About my second question about the
>>>>>> computing time, you say that the problem would be my memory, but could
>>>>>> you tell me any suggestion about how I can obtain better performance?
>>>>>> I am using CGAL 3.9 with visual studio 2010, in a Pentium(R) Dual-Core
>>>>>> CPU 2.10 GHz and 2GB RAM. On the other hand, I have the maximum value
>>>>>> (8190 MB) of virtual memory in my windows 7 option.
>>>>>
>>>>> To check whether it is memory, you should try with fewer points and see
>>>>> how
>>>>> the running time evolves.
>>>>>
>>>>> But first:
>>>>> * I assume you are using Exact_predicates_inexact_constructions_kernel,
>>>>> right?
>>>>> * Are you using Triangulation_3? Did you try Delaunay_triangulation_3?
>>>>>
>>>>> --
>>>>> Marc Glisse
>>>>>
>>>>> --
>>>>> You are currently subscribed to cgal-discuss.
>>>>> To unsubscribe or access the archives, go to
>>>>> https://lists-sop.inria.fr/wws/info/cgal-discuss
>>>>>
>>>>>
>>>>
>>>
>>>
>>> --
>>> Andreas Fabri, PhD
>>> Chief Officer, GeometryFactory
>>> Editor, The CGAL Project
>>>
>>> phone: +33.492.954.912    skype: andreas.fabri
>>>
>>> --
>>> You are currently subscribed to cgal-discuss.
>>> To unsubscribe or access the archives, go to
>>> https://lists-sop.inria.fr/wws/info/cgal-discuss
>>>
>>>
>>
>
>
> --
> Andreas Fabri, PhD
> Chief Officer, GeometryFactory
> Editor, The CGAL Project
>
> phone: +33.492.954.912    skype: andreas.fabri
>
> --
> You are currently subscribed to cgal-discuss.
> To unsubscribe or access the archives, go to
> https://lists-sop.inria.fr/wws/info/cgal-discuss
>
>