Unanswered Questions
43 questions with no upvoted or accepted answers
14
votes
0
answers
290
views
Unpopular/Obscure solvers/algorithms that you used
There are many (numeric) optimizers which solve some subset of the set of multi-objective, black-or-grey-or-white box, robust, stochastic, mixed-integer, non-linear, non-smooth, manifold-constrained ...
- 5,513
7
votes
0
answers
100
views
Which Constraint solver is extensible to CSP algorithms?
I am novice to constraint programming and I need to implement the following algorithms.
Backtacking
Conflict-based backjumping
AC partial lookahead
MAC
Forward checking
Forward checking + dom
...
- 87
6
votes
0
answers
609
views
Adequate SDP solvers for large problem instances
I have previously used MOSEK for all my SDP needs. Recently, though, I am having a hard time trying to solve some large problems, due to lack of memory. In similar questions around the forum, SCS has ...
- 1,955
6
votes
0
answers
119
views
Issue of Dense columns in the formulation
I'm working on a price-selection model where we need to identify price point for each time-period (could be day/week). Objective of the model is to figure out optimal price-point for each time-point ...
- 994
6
votes
0
answers
102
views
How to communicate number of integer combinations to a user
I'm working on a nifty little feature for our next release, i.e., to print the number of possible integer combinations left during branch and bound.
This is really handy for the user because they ...
- 5,513
6
votes
0
answers
875
views
Solver for Go Programming Laguage
Has anyone used MIP solvers (open source or commercial) with Go language https://golang.org/? I am looking for a solver for simple linear MIPs for network flows and set cover types of problems.
- 141
5
votes
0
answers
140
views
Materials or sample code for column generation book (GERAD 25th Anniversary Series)
As far as I know, one of the interesting resources to learn the basic concept of the decomposition methods is column generation book (GERAD 25th Anniversary Series), which has been mentioned in some ...
- 10k
5
votes
0
answers
1k
views
What is the difference between root relaxation and LP relaxation
(I apologize. I saw this question but, I do not know these may be the same or not.)
I am trying to solve a MIP problem and have an issue about that. The problem's LP relaxation has the objective ...
- 10k
5
votes
0
answers
213
views
All optimal solutions
I have a following problem:
If I have some function $aX+bY+cZ+mD+nF$ and I want to maximize it and have some constraints, how can I find ALL solutions for this maximum value of the function?
To sum ...
- 5,513
4
votes
0
answers
103
views
lp_solve gives a very infeasible solution
I am trying to solve the following integer linear program using lp_solve: (there is no objective, so this is just asking about feasibility)
...
- 141
3
votes
0
answers
65
views
Adding synchronisation constraint in Prize-collecting VRPTW
I am solving a Prize Collecting VRPTW. In my problem, each node represents a visit that needs to be made within a certain time window, and the "prize" for each node is the time spent at the ...
- 33
3
votes
0
answers
265
views
Can Pyomo be linked with Google's GLOP or CP-SAT solvers?
Pyomo can be linked with several solvers Open source and commercial ones.
I was wondering if Pyomo can be linked with Google's GLOP or CP-SAT solvers?
- 3,059
3
votes
0
answers
69
views
Indeterminacy Reduction for MINLP
I am considering a Mixed Interger NonLinear Program (MINLP), and using a solver to obtain admissible solutions.
Is there a general method to reduce indeterminacy of solutions (e.g. by adding ...
- 424
3
votes
0
answers
184
views
Are there hybrid metaheuristic-solvers to solve combinatorial optimization problems?
I have a problem which is formulating a linear program. To solve large instances I implement a metaheuristic to solve my problem. In my problem, I have two objective functions.
With my linear program, ...
- 5,513
3
votes
0
answers
146
views
Availability of library for solving generalized network flow problems
I need to solve a large-scale generalized network flow problem.
For reference, it is a pure network-flow model with the exception that arcs have a positive coefficient applied to flow on them. In my ...
- 3,059