GNU Linear Programming Kit

#1

Post by dvfjsdhgfv » Sun, Jun 30, 2019, 8:29 AM UTC

GNU Linear Programming Kit
en.wikibooks.org

Re: GNU Linear Programming Kit

#2

Post by 6thaccount2 » Sun, Jun 30, 2019, 4:40 PM UTC

It's really good to have GLPK & Open Solver (COIN OR Project) available for the public.

The commercial solvers (CPLEX, GUROBI, XPRESS) might be significantly more robust and fster, but they are unbelievably expensive even for a non-commercial license.

Open-Solver allows me to prototype on small models without getting a loan.

Re: GNU Linear Programming Kit

#3

Post by sansnomme » Sun, Jun 30, 2019, 5:34 PM UTC

6thaccount2 wrote: post #2

It's really good to have GLPK & Open Solver (COIN OR Project) available for the public. The commercial solvers (CPLEX, GUROBI, XPRESS) might be significantly more robust and fster, but they are unbelievably expensive even for a non-commercial license. Open-Solver allows me to prototype on small models without getting a loan.

Give MSFT's Z3 a try too.

Re: GNU Linear Programming Kit

#4

Post by analognoise » Sun, Jun 30, 2019, 5:38 PM UTC

Would this be useful in solving the kinds of constraints found in ECAD layout?

Re: GNU Linear Programming Kit

#5

Post by 6thaccount2 » Sun, Jun 30, 2019, 5:50 PM UTC

sansnomme wrote: post #3

6thaccount2 wrote: post #2

It's really good to have GLPK & Open Solver (COIN OR Project) available for the public. The commercial solvers (CPLEX, GUROBI, XPRESS) might be significantly more robust and fster, but they are unbelievably expensive even for a non-commercial license. Open-Solver allows me to prototype on small models without getting a loan.

Give MSFT's Z3 a try too.

Thanks for the tip... I'll check it out.

Re: GNU Linear Programming Kit

#6

Post by dbcurtis » Sun, Jun 30, 2019, 5:50 PM UTC

analognoise wrote: post #4

Would this be useful in solving the kinds of constraints found in ECAD layout?

Unlikely. Most interesting problems in ECAD are non-linear.

Re: GNU Linear Programming Kit

#7

Post by 6thaccount2 » Sun, Jun 30, 2019, 5:54 PM UTC

analognoise wrote: post #4

Would this be useful in solving the kinds of constraints found in ECAD layout?

Can the problem be formulated in a linear way? When doing optimization you have a function that you are trying to minimize like the cost of dispatching power plants. If there is no exponents or trig functions (and whatever else that could make it non-linear) you can solve the problem while adding constraints.

GLPK can also do mixed-integer linear programming where some variables are integers like (0,1).

If you need to optimize something that is nonlinear, that requires something else I think, but read the doc.

Re: GNU Linear Programming Kit

#8

Post by spsx » Sun, Jun 30, 2019, 5:58 PM UTC

6thaccount2 wrote: post #2

It's really good to have GLPK & Open Solver (COIN OR Project) available for the public. The commercial solvers (CPLEX, GUROBI, XPRESS) might be significantly more robust and fster, but they are unbelievably expensive even for a non-commercial license. Open-Solver allows me to prototype on small models without getting a loan.

I believe they are all free for academic use. There is also SCIP, one of the fastest academic solvers but you also need a license for commercial use, although I think the license is much cheaper than CPLEX and Gurobi.

Re: GNU Linear Programming Kit

#9

Post by 6thaccount2 » Sun, Jun 30, 2019, 6:41 PM UTC

spsx wrote: post #8

6thaccount2 wrote: post #2

It's really good to have GLPK & Open Solver (COIN OR Project) available for the public. The commercial solvers (CPLEX, GUROBI, XPRESS) might be significantly more robust and fster, but they are unbelievably expensive even for a non-commercial license. Open-Solver allows me to prototype on small models without getting a loan.

I believe they are all free for academic use. There is also SCIP, one of the fastest academic solvers but you also need a license for commercial use, although I think the license is much cheaper than CPLEX and Gurobi.

I work at a non-profit and not a University, so I can't use them for free.

My very nice, but slightly used car cost me less money and it has been driven over an hour per day for 7 years. That makes those solvers very hard for me to justify outside of production where the license costs are worth every darn penny.

Re: GNU Linear Programming Kit

#10

Post by spsx » Sun, Jun 30, 2019, 6:53 PM UTC

6thaccount2 wrote: post #9

spsx wrote: post #8

Earlier quoted context omitted.

I believe they are all free for academic use. There is also SCIP, one of the fastest academic solvers but you also need a license for commercial use, although I think the license is much cheaper than CPLEX and Gurobi.

I work at a non-profit and not a University, so I can't use them for free. My very nice, but slightly used car cost me less money and it has been driven over an hour per day for 7 years. That makes those solvers very hard for me to justify outside of production where the license costs are worth every darn penny.

I totally agree. But if you are a non-profit you might be able to get a SCIP license for free, you just have to contact the people behind it. But if a moderate performance improvement is not that important for you then GLPK is definetly the best option.