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[Juan Carlos Lopez Alfonso <>]

Hi,

In all cases I run my simulations in Release mode and my concern is principally about the computing time. I am testing in a computer with only 2 GB of RAM, but I will use a powerful computer in some days. For this reason my concern is about the computing time.

Even when my set of points are 'degenerate' (in parallel planes), Can I always expect a result of Delaunay triangulations? How many time will I approximately expect?

You talk about the spatial sorting, and If I understand the meaning I cant use spatial sorting, because I have a fixed set of points and are in parallel planes.

Best regards and thank in advance

Juan Carlos

On Thu, Nov 24, 2011 at 5:25 AM, Monique Teillaud <> wrote:

Le 24/11/11 01:26, Juan Carlos Lopez Alfonso a écrit :

Hi all:

The documentation of Triangulation_3 says that constructions of Delaunay
triangulations with more than 10^7 points is compute in 87.4 seconds. In
my case, I have a set of points (3 500 000) in parallel planes and the
computing time is much greater than this (hours). On the other hand, the
same code in the same computer for a Triangulation_3 work very fast
(minutes), but for Delaunay_triangulation_3 is very slow and throw an
alloc exception (problem with memory).

Please, could anyone explain me the reasons of this problems?

Hi,

We usually don't run benchmarks on Triangulation_3, because such triangulations don't seem to be very useful in practice, and the computed triangulation depends on the order in which points are inserted.

For Delaunay triangulations, 'degenerate' input data (which are more likely to occur when points lie in parallel planes) are expected to yield larger running times than random data sets.

That said, I am afraid that we cannot explain anything without knowing the conditions of your experiments at all, eg.
- did you compile in release mode?
- how much memory has your computer?
- did you use spatial sorting?
- ...

Best,

--
Monique Teillaud
INRIA Sophia Antipolis - Méditerranée
http://www.inria.fr/sophia/members/Monique.Teillaud/

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