Questions tagged [or-tools]
Questions related to or-tools, Google's open-source software suite for optimization
176
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Job Shop Scheduling with Multiple possible machines for a task in CP-SAT
I am trying to convert the job shop scheduling example of CP-SAT, which goes as;
Below is a simple example of a job shop problem, in which each task is labeled by a pair of numbers (m, p) where m is ...
- 19
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50
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How to request shifts when nurses _don't_ work
So I am working on a variation of the nurse scheduler.
This includes then the ability to have nurses request when they are going to be on...
However, I need to be able to support requests for when ...
- 101
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50
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Convert sequence to succession matrix with CP-SAT
Say I have a sequence [3,1,0,2], where each element is a decision variable, i.e. I decide upon an optimal sequence of numbers. Is there an appropriate way to convert this sequence to a 2D succession ...
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833
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How to avoid similar solutions?
I have a problem like this
$x_1 +x_2 +x_3 =10$
let's assume $0 \leq x_i \leq 10$
It is obvious that this problem has more than one solution
For example :
Solution 1 : $x_1 =0 , x_2= 1 , x_3 =9$
...
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84
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Cumulative constraint with a window
I have a decision variable R, indexed by n over N, where R[n] is equal to some integer value. I want a constraint that, for a specific window size, e.g. 5, gives a maximum to the summed values inside ...
2
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1
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120
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Optimizing a Route Selection Problem with Multiple Constraints and Objectives
I'm developing a solution to optimize a vehicle routing problem where each stop has an associated score (priority), specific geo coordinates, and a required stop duration. The goal is to maximize the ...
- 131
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97
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Assignment of colored boxes to groups
I am working on a problem that I think can be solved as an extension to the assignment problem, but am open to hear about other ways to solve.
PROBLEM
There are a lot of colored boxes. For each color ...
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Information shared among workers in OR-tools CP-SAT
I stumbled upon this video while using OR-Tools CP-SAT solver
https://www.youtube.com/watch?v=lmy1ddn4cyw
At around 12:10, the part of multithreaded solvers starts. I understand these solvers are ...
2
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1
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237
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CP-SAT: Workarounds for OnlyEnforceIf with Linear Expressions
Background
I've written a solver that selects a subset of people from a larger pool such that the subset has at least X people per attribute (Gender/Job/Country etc. X differs per attribute).
This ...
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84
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Vehicle Routing Problem OR-tools - Distance between solutions / vehicles
I have an alternative problem which I reckon can be solved using OR-tools. For this problem, apart from the distance between nodes within a solution, I also need the distance between the n-th node of ...
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113
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Solving a weighted XOR-SAT problem
I want to solve a variant of the weighted XOR-SAT problem. Concretely,
Given $n$ boolean variables $x_1,\ldots,x_n$ each of which is assigned a non-negative cost $c_1,\ldots,c_n\in\mathbb{R}_{\ge 0}$ ...
- 123
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86
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Implementing soft time window constraints with time_matrix dependent on vehicle types
I am solving a CVRPTWPD using Google ORTools. Here, objective is to minimize the travelled distance and not time.
I have start locations for each vehicle but arbitrary end locations are possible. I ...
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119
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How to set the parameters for GLOP for a DUAL_FEASIBLE case
Now I have a linear programming model, I have tried to formulate this model with or-tools, and then solve it with the GLOP but failed.
After reaching the 15-minute time limit, the status of GLOP is ...
- 105
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Google Cloud Fleet Routing... what types of VRPs does it cover?
I'm familiar with solving VRPs in Google's ortools. Has anybody used Google's new Cloud Fleet Routing capability (separate from ...
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240
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Or-Tools：glop or clp to solve a LP
I have a linear programming problem where I use Or-Tools interface in Java for modeling. When using SCIP, I sometimes encounter memory errors and the solving time is relatively long. Later, I changed ...
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