May 2015 - PPL-devel - BUGSENG Mailman

Merging Convex Hulls
by Monty Hall 04 Jun '15

04 Jun '15

Is this possible on PPL? If so, how is it done? Suppose I have 2 sets of input generators. I compute the convex hull/faces for both via double description. My question is, would this be "concatenation" operation? If so, it doesn't just concatenate the list of input generators and then performs double description does it? Here's what I'm wondering, I often have in input that takes a long time to process. I was wondering if I could split the input into two perform double description. And then merge the convex hulls/hyperplanes together to get a final solution. Divide and conquer so to speak. Not sure if this would be faster than processing the input all at once. Thanks, M

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PPL ranking functions
by Kafle, Bishoksan (ARC-TI)[SGT, INC] 21 May '15

21 May '15

Hi there, I have a question about ranking functions, which hopefully you can clarify me. I am using PPL-ciao prolog interface. The predicate ppl_one_affine_ranking_function_MS_C_Polyhedron(H,RF) gives a single ranking function if there exists one. But I would like to have the possibility of getting more than one ranking functions. The predicate ppl_all_affine_ranking_functions_MS_C_Polyhedron(H,RFs) gives a polyhedron which represent a space of all affine ranking functions but how can one generate or enumerate them systematically? Any help on this would be highly appreciated. Many thanks Bishoksan

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can you create a brew recipe so that mac users can install PPL automatically ?
by Francois Berenger 21 May '15

21 May '15

Cf. http://brew.sh/ for the homebrew package manager for macos. -- Regards, Francois.

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Re: [PPL-devel] PPL ranking functions
by aeflores 19 May '15

19 May '15

Hi Bishoksan, One thing that I do to obtain multiple ranking functions is to call: ppl_all_affine_ranking_functions_MS_C_Polyhedron(H,RFs) And then obtain the points of the resulting polyhedron ppl_Polyhedron_get_generators(RFs, Gen) So if you have a loop defined as [A>=0,B>=0,A'=A-1,B'=B-1] the points of the resulting polyhedron will be 1*A and 1*B which are both independent ranking functions. I hope that helps. Best, Antonio Flores Montoya On 05/19/2015 12:00 PM, ppl-devel-request(a)cs.unipr.it wrote: > Re: [PPL-devel] PPL ranking functions

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