Hi UserCplex,

can you tell us, what the question is that you really want to anwer? Maybe, we need no projection to do so.

By the way, I used TOSimplex and found out that your problem has 125 different feasible solutions for the integer variables.

Best regards,
Thomas

I guess, 0.0714285714285714 means 1/14 and 0.428571428571429 means 3/7 (never use such floating point numbers in exact arithmetic). If I multiply the corresponding constraints by 14 on the one hand and by 7 on the other hand and then make the right hand side integer, I get 2145 as optimal solution. ...

./configure --prefix=/opt/ppl --enable-ppl_lcdd This would usually require sudo for make install, because /opt is owned by root. Thanks for pointing this out. I typiclaly chown the folders before, e.g.: sudo mkdir /opt/ppl sudo chown opfer. /opt/ppl Then you don't need sudo for the installation pro...

First, please install M4: apt install m4 Then see if configure has further errors. Also, on Ubuntu, I would not install to the default path. I'd rather do something like ./configure --prefix=/opt/ppl --enable-ppl_lcdd Then after "make" and "make install", you should be able to ca...

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. Did you use the parameter "--enable-ppl_lcdd" for configure? polymake does not use ppl in the floating-point mode yet, rather for rational numbe...

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? Yes, sure. But as I said, this was just a test (completely without polymake). Here is what I did: 1. Configure, compile and install PPL (conf...

I just did another test: I used PPL (Parma Polyhedra Library) to calculate the H-representation from these 4722 points. It took around 20 seconds to generate 414 exact rational (in)equalities. Do you know whether this number is correct?

Best regards,
Thomas

Is there any software you are aware of that computes facetial inequality and equations of the affine hull using faster but less accurate floating point arithmetic when it is provided with the set of lattice points? As far as I know, both cdd and lrs should be able to do this. But you should also be...

I think this has 2 reasons: 1. polymake uses exact arithmetic. Exact calculations are much slower than floating point arithmetic used in CPLEX. 2. If I remember correctly, polymake currently uses convex hull algorithms to enumerate the lattice points. A year ago, I wrote a Cut&Branch algorithm t...

Yes, perhaps I should look at projecting out the continuous variables. Some of these variables are /implicitly/ binary though. Will there a performance gain in polymake if I explicitly declare in the .lp file variables to be binary (that are implicitly so)? I cannot answer this for sure, but I thin...