Questions tagged [scip]

SCIP is a source-open solver for (among others) MILPs, MINLPs, ... ask questions about usage, bugs, interfaces, behavior.

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SoPlex basis file format

I'm running SoPlex from the command line to solve some linear programming problems. I'd like to get the basis of the solution, so I use the --writebas flag. However,...
  • 213
4 votes
0 answers

Changing a parameter while branching in SCIP

I use pyscipopt. I know how to add constraints while branching using handlers (kind of), but now I want also to change some parameters. I imagine is similar, but couldn’t found an example. What I want ...
  • 403
21 votes
3 answers

Using Neural Networks For Solving Optimization Problems

Recently, I came across the below paper and found it very interesting. Solving Mixed Integer Programs Using Neural Networks; The idea is to use (train with neural ...
1 vote
1 answer

Importing data into SCIP solver

Is it possible to import data into SCIP from Excel (and then export results to Excel)? If yes, how can I do it?
  • 65
1 vote
0 answers

Doesn't Pyscipopt handle nonlinear objective functions?

I am trying to solve a large-scale nonlinear problem. Below is the objective function coded for pyscipopt. I have some loops over a list of tuples (r,p,s) in the list RouteTimeStop, and the only ...
  • 1,229
7 votes
2 answers

Can I use 'SCIP' solver for PYOMO?

I have an MINLP problem to solve where I was initially using 'ipopt' solver but the solution was not sticking to 'binary/boolean/integer' domain type for a variable. I am not sure which free solver ...
1 vote
1 answer

Branch-and-Price: return gap using SCIP

I implemented a branch-and-price tree in python. I would like to stop the process after 5 hours and return the gap in % between the best integer solution found so far and the optimal solution. How ...
9 votes
2 answers

Warm-start SCIP with a solution

I am trying to solve a MIP using SCIP. I let my solver run for some initial time-bound - let's say 10min. After 10min, I check if the problem is solved to optimality or 1% gap. If not, then I would ...
19 votes
3 answers

Column generation stabilisation

Has anyone performed a benchmark of the various stabilisation techniques in column generation? Which ones perform better for set pack/partition/cover problems like VRP? And are there theoretical ...
  • 1,225