-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Hello, a short question: What is the method to use when computing the convex hull of a C_Polyhedron? Currently I try minimized_generators. Best regard, Stefan - -- Stefan Schupp M.Sc. RWTH Aachen University Computer Science Department, Informatik 2 D-52056 Aachen, Germany http://www-i2.informatik.rwth-aachen.de/i2/schupp/ Tel.: +49 241 80 21243 -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.22 (Darwin) Comment: GPGTools - https://gpgtools.org iQEcBAEBCgAGBQJUGvyCAAoJEFPSi5GyofDjhm8H/1hs1zqXzBnKohwlnwhM3ErV I17/lrNrkYAcvPUvXHMR1DdVYmN/80vad1nuwJkzNQe/luB7iO4jh0HsXSPPjh4j CDYSkzoP6P0Iu/13BSu3VLu8tnENoETN/yDsrIVNdKhk9JWCyu6mruUVP9Io7g8K PA3aqlXFikPX2Bekm4PX2Kaz49ojr7zQc+BNCDGijFK/r85PX1zeBflotk4xQ3Zp rQU5T1g0V1W7cquCW4r+dgar74YRf2zULywUN9NtSk0G2pfM3wOuOaQP9f6TyJJ8 jrxAooPGfLYdkCzN49DZU6Z7k3stP1I7vaPyeIi/SVRUKII+6mNn0mfM7+zeAPA= =8b3u -----END PGP SIGNATURE-----
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello Stefan. On 09/18/14 17:38, Stefan Schupp wrote:
a short question: What is the method to use when computing the convex hull of a C_Polyhedron?
I am not sure I understand what you mean. A C_Polyhedron is a convex polyhedron, i.e., i.e. it coincides with its own convex hull. In other words, computing the convex hull of a C_Polyhedron is a no-op.
Currently I try minimized_generators.
What are you trying to achieve, exactly? Kind regards, Roberto - -- Prof. Roberto Bagnara Applied Formal Methods Laboratory - University of Parma, Italy mailto:bagnara@cs.unipr.it BUGSENG srl - http://bugseng.com mailto:roberto.bagnara@bugseng.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iEYEARECAAYFAlQb10gACgkQiBRXy7WUQ5JkugCeMCbpXbSJFoQsPXinRnZFvhjd cR0AnA+FtX2e0qIXi5xiwiiyZeIt6Y4y =wJoN -----END PGP SIGNATURE-----
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Hello Roberto, my goal was to calculate some kind of Minkowski sum. A very unefficient and simplistic approach would be to create the decomposition of the addition (So simply add all vertices of P1 to all vertices of P2) and after that compute the convex hull to drop interior points. As my polyhedra are represented by Pointgenerators I create a new polyhedron by applying the method above to the generators. I thought after that a minimization of the generator set should do the trick. Best regards, Stefan Am 19/09/14 09:12, schrieb Roberto Bagnara:
Hello Stefan.
On 09/18/14 17:38, Stefan Schupp wrote:
a short question: What is the method to use when computing the convex hull of a C_Polyhedron?
I am not sure I understand what you mean. A C_Polyhedron is a convex polyhedron, i.e., i.e. it coincides with its own convex hull. In other words, computing the convex hull of a C_Polyhedron is a no-op.
Currently I try minimized_generators.
What are you trying to achieve, exactly? Kind regards,
Roberto
- -- Stefan Schupp M.Sc. RWTH Aachen University Computer Science Department, Informatik 2 D-52056 Aachen, Germany http://www-i2.informatik.rwth-aachen.de/i2/schupp/ Tel.: +49 241 80 21243 -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.22 (Darwin) Comment: GPGTools - https://gpgtools.org iQEcBAEBCgAGBQJUG9oGAAoJEFPSi5GyofDjRrUH/168+WoqBJ7hauykA/en9+J3 HjeNhazf73m15OmL35x3HuDcL7R/cB2lK6Bx/6/wWy87XIaA1Lu/pMLB7gycCWW0 OUQi2qKkfACkMeCd+30E2egXtutJuWUlS1JCiHj8aC1cVqbSi/TDar5BovK7Mhzs fxuq06bWYTMPjjXWBwSYw1IdnY1aAPztbwfjgZyGMaTN/CJHzptnvc4PbXSKFB84 2YpVnUscX9Y7TQkB2VszuZ58oIbMV17M4sNnUsy/AfSMBfU9ArXEgy5VBkMTzi+w gHdc5wGmpFcOh+Z4SiN/5lgqg6YkBPVwLY0N5WZXv216w6fMLmBm/KIKmOSkkVI= =AlOI -----END PGP SIGNATURE-----
On 09/19/14 09:23, Stefan Schupp wrote:
my goal was to calculate some kind of Minkowski sum. A very unefficient and simplistic approach would be to create the decomposition of the addition (So simply add all vertices of P1 to all vertices of P2) and after that compute the convex hull to drop interior points.
As my polyhedra are represented by Pointgenerators I create a new polyhedron by applying the method above to the generators. I thought after that a minimization of the generator set should do the trick.
Minimization of the generator set will indeed remove all redundant generators, which in your case are the interior points you want to get rid of. So, yes: minimized_generators() seems to be the right method for you. Kind regards, Roberto
Am 19/09/14 09:12, schrieb Roberto Bagnara:
Hello Stefan.
On 09/18/14 17:38, Stefan Schupp wrote:
a short question: What is the method to use when computing the convex hull of a C_Polyhedron?
I am not sure I understand what you mean. A C_Polyhedron is a convex polyhedron, i.e., i.e. it coincides with its own convex hull. In other words, computing the convex hull of a C_Polyhedron is a no-op.
Currently I try minimized_generators.
What are you trying to achieve, exactly? Kind regards,
Roberto
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-- Prof. Roberto Bagnara Applied Formal Methods Laboratory - University of Parma, Italy mailto:bagnara@cs.unipr.it BUGSENG srl - http://bugseng.com mailto:roberto.bagnara@bugseng.com
participants (2)
-
Roberto Bagnara -
Stefan Schupp