Questions tagged [modeling-languages]
For questions related to (algebraic) modeling languages such as AMPL and GAMS, which facilitate the process of translating an optimization model written in algebraic form to the matrices, vectors, and other data needed by general-purpose solvers.
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What is the purpose of libraries like Pyomo and Google OR tools?
I'm new to the OR world, and trying to learn the various tools available. I originally thought that Pyomo and Google OR tools were open source alternatives to commercial solvers like Gurobi or CPLEX.
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Comparison of Algebraic modelling languages and general programming languages
Some optimization software/frameworks (commercial or open-source) such as AMPL, GAMS, Cplex, ... have a specific Algebraic modelling language. Some of them have another type of programming that uses ...
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From a performance/speed perspective, does the programming language matter if the solver used is the same?
Perhaps a silly question, I know... But just wondering if the programming language has an impact here if the solver used is the same? For instance, the same model formulation being solved using Gurobi ...
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I've formulated my optimization model; now what?
I've formulated my linear/nonlinear/integer/mixed-integer optimization problem in algebraic form (possibly with the help of the folks on this site).
Now what? How do I solve it?
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How to get GAMS's solvers to work from Pyomo?
I want to run a model written in Pyomo language with CPLEX solver of GAMS.
However I get the following error:
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Understanding the AMPL Solver LIbrary within Pyomo
For anyone familiar with the Pyomo book, it occasionally makes reference to the AMPL Solver Library, and to my understanding, if you can manage to hook up to the solver library then you are able to ...
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Modelers and modeling languages: how do you choose, and which features do you use?
There are many modeling languages and APIs around. One or more per solver, plus many that target multiple solvers: AMPL, GAMS, PuLP, JuMP, Pyomo...
Among all these possibilities, why did you pick a ...
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Does a modeling language that generates SAT instances exist?
Nowadays, we enjoy the expressivity of modern modeling languages. However, does it exists a modeling language that takes in input a declarative problem definition (like AMPL or MiniZinc, or similar),...
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Is JuMPeR good enough for Robust Optimization problem?
I'm a graduate student studying Robust Optimization (RO).
So far, I've been studied the theoretic point of RO, and now I am looking for an actual tool for solving RO problems, both for practice and ...
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How to assign values to array in CPLEX with C++?
I am new to CPLEX. I am using CPLEX with Xcode in macOS.
I have three arrays (known parameters used in optimisation) which I define as
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Solver options in Pyomo as long as using the NEOS solvers
I am working on a scheduling problem that is already coded in Pyomo. To solve the problem, I have used the NEOS solver, CPLEX. Now, to test and run some of the instances, I need to call some CPLEX ...
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No executable found for solver 'ipopt
I know that there are some questions concerning this type of error, for example, this link.
I first installed the latest version of ipopt through command line into my Pyomo environment and got the &...
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Automatic Reformulation Tools For AML Programs
Are there any tools to transform programs written in an algebraic modeling language like GAMS,AMPL,... into a different formulation.
E.g. there is a quadratic constraint $\sum_j b_i b_j = N, b \in \...
- 153
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Using networkx predecessors in Pyomo initialize method
I am working on the directed graph by using the Networkx package and what I need is to use its predecessors' method on an optimization model. Let's say, there exists a directed graph with just $12$ ...
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Discrepancy between CPLEX interface solution and C API
I have a C API program uploaded here in Dropbox that is an LP. Here is the problem: When I compile the C file it gives me "1017 Not available for mixed-integer problems" while the problem is ...
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How to use NEOS without using Pyomo
I am new to modelling language and specifically NEOS server. I aim to solve MINLP using Baron, through the NEOS server. So, far I have been able to write model file, data file and command file as ...
user4387
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Which combinations of python modeling libraries and solvers support logarithmic objective functions?
As I understand it, if a modeling library (pyomo, amplpy, cvxpy, etc.) allows one to define a logarithmic objective function a solver may not support it. And even if a solver does support a ...
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Optimization solver that satisfies variable values within set membership
Is there a solver that can handle an AMPL model of this sort:
...
