Questions tagged [or-tools]
Questions related to or-tools, Google's open-source software suite for optimization
176
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Or-Tools: Process finished with exit code 132 (interrupted by signal 4: SIGILL)
Now I am using Or-Tools via the Java interface to solve a LP.
ModelBuilder model = new ModelBuilder();
ModelSolver solver = new ModelSolver("SCIP");
...
- 105
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4
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570
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Google-OR Tools: Assignment minimizing overlapping members
I'm rusty on constraint optimization and am looking for help in this particular use case. There are individuals who are each member to several teams. This is a fixed many-to-many relationship and is ...
- 113
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380
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OR-Tools CP-SAT solver: is it possible to name a constraint like in GUROBI
I try to implement cp model with OR-tools CP-SAT solver. Please, is it possible to name constraints for being able to manage conflict later like for variables:
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How to cmpute IIS using the Or-Tools solver?
I'm trying to solve a MIP using Google Or-Tools, but it's showing that the model is infeasible. I'd like to know if there is a convenient way to analyze which constraint or variable bounds are causing ...
- 105
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173
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Output a readable model file and control the solver parameters in Or-Tools
I am using Java to call the API of or-tools in IntelliJ IDEA to solve a mixed-integer programming problem. There are some modeling statements such as ...
- 105
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2
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Evaluation of linear expression with docplex based on a solution
For a CpModel using docplex, is there any function to evaluate a linear expression based on the variables values in the final solution?
For example, for ...
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1
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164
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Non integer linear objective in or-tools CP-SAT
It seems that or-tools' CP-SAT solvers allows for non-integer coefficients in a linear objective expression. Am I correct, or is it just that the solver doesn't check for integrity and rounds the ...
- 11
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104
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Scheduling repeated tasks with minimum duty cycles
Several tasks need to run repeatedly in a channel, one at a time, over a repeating time frame of length $T$. Associated to each task $i$ is the duration $L_i$ the task will take to run, and a maximum ...
- 111
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91
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Formulating assignment problem with people attributes that need to be balanced per assignment attribute in or-tools, CP-sat
I'm trying to do an assignment problem with the following characteristics:
I have two sets that need to be matched with each other, set A (Students) and set B (Class combinations). Set A and B have ...
- 41
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166
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Using binary variable or integer variable in Constraint Programming (CP)?
I am trying to solve an assignment problem by Constraint Programming (CP). Let us consider a task assignment problem that have $|M|$ tasks and $|N|$ machines, each task has different processing time ...
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Numerically stable way to optimize a lexicographical preference between two objective functions?
I am solving a mixed-integer program whose decision variables are $x \in \{0, 1\}^n$ and $y \in \mathbb{R}^m$, where $0 \leq y_j \leq u_j$ for constant upper bounds.
My primary objective function is ...
- 564
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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
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123
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Team Orienteering Problem with Time Windows infeasible using CP-SAT solver in Google OR-Tool
I am developing a TOPTW where there are a set of N nodes. Each node i is associated with a visit time, which is also the score Si. The starting point and the end point of each tour is fixed, which is ...
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1
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Are there any hidden differences in OR-Tools' default parameters for a MIP model in Python vs C++?
or-tools-discuss cross post here.
As a disclaimer -- I am very aware that OR-Tools' Python code are just wrappers around their C++ source code. I'm just getting an odd discrepancy between a model ...
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Rearrange 'x' piles of items into eight possible locations/bins based on item color and length
I have an optimization problem that I believe is a variant of the 'bin packing problem with precedence', but I'm unsure of if that is the correct paradigm to work with and I'm not having a huge amount ...
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