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by UserCplex
10 Mar 2019, 12:55
Forum: General Discussion
Topic: Enumerating all integer feasible points, CPLEX vs Polymake
Replies: 18
Views: 723

Re: Enumerating all integer feasible points, CPLEX vs Polymake

Hi Opfer/Gawrilow, I created a lp2polyfloat.sh file to automate the task of reading in an LP file and computing the facets "quickly" by using Floats instead of Rationals as suggested earlier in this thread. The script file content is: use application "polytope"; use vars qw($f $p $s); $f=lp2poly('pr...
by UserCplex
25 Feb 2019, 11:00
Forum: General Discussion
Topic: Enumerating all integer feasible points, CPLEX vs Polymake
Replies: 18
Views: 723

Re: Enumerating all integer feasible points, CPLEX vs Polymake

Thomas Thank you very much. Following your instructions, I have indeed been able to run ppl_lcdd from the bin folder and link it to test2.txt file you shared. Yes, gawrilow was also right. I had to do sudo make install. I obtain an output that lists: 414 40 integer <<and equations?>> Is there a way ...
by UserCplex
25 Feb 2019, 10:22
Forum: General Discussion
Topic: Enumerating all integer feasible points, CPLEX vs Polymake
Replies: 18
Views: 723

Re: Enumerating all integer feasible points, CPLEX vs Polymake

Gawrilow and Thomas: Below is the log from ./configure --enable-ppl_lcdd Does anything obvious stand out for you in terms of missing dependencies? I am rather new to ubuntu/linux. I can understand if you don't want to get into this. I will go to ppl website and look through their support files as we...
by UserCplex
25 Feb 2019, 09:38
Forum: General Discussion
Topic: Enumerating all integer feasible points, CPLEX vs Polymake
Replies: 18
Views: 723

Re: Enumerating all integer feasible points, CPLEX vs Polymake

Thomas, Thanks. But it is not working for me :-( I downloaded ppl from their website, then did configure with the enabling on, make and install. Then, after restarting the machine, ppl_lcdd says "bash: ppl_lcdd command not found" Is there anyway ppl can be run via polymake? In the opening credits of...
by UserCplex
25 Feb 2019, 07:31
Forum: General Discussion
Topic: Enumerating all integer feasible points, CPLEX vs Polymake
Replies: 18
Views: 723

Re: Enumerating all integer feasible points, CPLEX vs Polymake

Thomas, I am simply unable to get such results at my end. Could you please share with me the steps you take to get the facetial representation in 20 seconds? At my end, I have the files (within the zip file specified in the OP) containing the lattice points in a folder. From within that folder, I ru...
by UserCplex
24 Feb 2019, 15:17
Forum: General Discussion
Topic: Enumerating all integer feasible points, CPLEX vs Polymake
Replies: 18
Views: 723

Re: Enumerating all integer feasible points, CPLEX vs Polymake

Thomas, Thanks. I have very rudimentary knowledge about floating point vs exact arithmetic. Due to the excessive time Polymake takes to figure out lattice points, my preferred method thus far has been to use cplex to quickly enumerate the points (using faster but less accurate floating point arithme...
by UserCplex
23 Feb 2019, 11:55
Forum: General Discussion
Topic: Enumerating all integer feasible points, CPLEX vs Polymake
Replies: 18
Views: 723

Enumerating all integer feasible points, CPLEX vs Polymake

Hello, I am noticing a big difference in the time taken to enumerate integer feasible points for a bounded integer program between CPLEX and Polymake. Attached is an integer program, "problemIP.lp". On running this through the attached "populate.c" cplex code file, I am able to obtain the 4722 integ...
by UserCplex
02 Mar 2018, 10:52
Forum: Helpdesk
Topic: Running into error with 3.2 installation
Replies: 13
Views: 4070

Re: Running into error with 3.2 installation

Just a short information regarding ppl: Ubuntu 16.04 provides ppl version 1.1 while polymake 3.2 needs version at least 1.2. So it does make sense that polymake 3.0 can work with the installed ppl but polymake 3.2 cannot. Hello blorenz Could you let me know how on ubuntu I can install ppl version 1...
by UserCplex
02 Mar 2018, 10:47
Forum: Helpdesk
Topic: Discrepancy in computing facets of a mixed integer program
Replies: 29
Views: 5896

Re: Discrepancy in computing facets of a mixed integer program

Hi gawrilow Yes, I did not add the AFFINE_HULL listings. The problem I am solving is not full dimensional. So, it is indeed the case that I might have had to add those. Let me think about this. I will do a check later on. But I think I am beginning to make sense of the output of polymake. In 3 dimen...
by UserCplex
02 Mar 2018, 01:43
Forum: Helpdesk
Topic: Discrepancy in computing facets of a mixed integer program
Replies: 29
Views: 5896

Re: Discrepancy in computing facets of a mixed integer program

Could you please reformulate this claim as a self-contained reproducible task, like this: "Given a system of linear inequalities A*x <= B and objective function C, I expect the optimal solution V attained with x = X, with all A, B, C, V and X specified as rationals or integers." Then we can debug i...

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