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Hi Tushar.<br>
<br>
There is one implementation of the convex hull for C_Polyhedra in
the PPL, based on the "usual" double description conversion
procedure. In principle, many alternative implementations can be
obtained by using finer granularity operators. However, no sensible
advice can be given for the "general case", since the efficiency is
known to be highly dependent on the specific input.<br>
<br>
You can also have a look to the following paper, where (among other
things) there is a comparison of the performance of many polyhedra
libraries on the convex hull problem:<br>
<br>
B. Assarf, E. Gawrilow, K. Herr, M. Joswig, B. Lorenz,
A. Paffenholz, and T. Rehn. polymake in linear and integer
programming. Technical Report arXiv:1408.4653 [math.CO], August
2014.<br>
<br>
<a class="moz-txt-link-freetext" href="http://arxiv.org/abs/1408.4653">http://arxiv.org/abs/1408.4653</a><br>
<br>
Regards,<br>
Enea Zaffanella.<br>
<br>
<br>
<div class="moz-cite-prefix">On 01/29/2016 08:31 PM, Tushar Sharma
wrote:<br>
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<p>Hi all,</p>
<p><br>
</p>
<p>I am using C_Polyhedron to perform abstract interpretation.
The polyhedrons I am dealing with take a lot of time to
perform convex hull. The convex hull spends a lot of time in
add_and_minimize operation. I was wondering if there is an
alternate implementation in PPL 1.1 (or some other unstable
version), that performs hull operation using CLP so that I can
compare the two implementations.</p>
<p><br>
</p>
<p>Thanks,</p>
<p>Tushar Sharma</p>
<p>Graduate Student</p>
<p>Computer Sciences</p>
<p>University of Wisconsin-Madison</p>
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