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Questions tagged [pyomo]

Pyomo is a Python-based open-source software package that supports a diverse set of optimization capabilities for formulating, solving, and analyzing optimization models.

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Multi-objective optimization example Pyomo

Any example for multi-objective optimization in Pyomo? I am trying to minimize 4 Objectives (Non Linear) and I would like to use pyomo and ipopt. Have also access to Gurobi. I want to see even very simple example where we try to optimize for two…
Golf Kilo Bravo
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Performance of pyomo to generate a model with a huge number of constraints

I am interested in the performance of Pyomo to generate an OR model with a huge number of constraints and variables (about 10e6). I am currently using GAMS to launch the optimizations but I would like to use the different python features and…
Dimitri Tomanos
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pyomo + reticulate error 6 the handle is invalid

I'm trying to run a pyomo optimization and I get the error message [Error 6] The handle is invalid. Not sure how to interpret it, looking around it seems to have something to do with privileges but I don't really understand it. Find below the…
lrnzcig
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Pyomo ValueError: Invalid constraint expression

I am writing a pyomo integer programme with a constraint of the form: def example_rule(model, j, t): value = sum(model.x[j,i]*(util[i][t]) for i in model.F) return 0 <= value <= 1 model.onelateral = Constraint(model.L, model.T,…
fishy321
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How to set Pyomo solver timeout?

How to set the timeout for Pyomo solve() method ? More specifically, to tell pyomo, after x seconds, return the optimal solution currently found ?
zyzo
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Pyomo: Access Solution From Python Code

I have a linear integer programme I want to solve. I installed solver glpk (thanks to this answer) and pyomo. I wrote code like this: from pyomo.environ import * from pyomo.opt import SolverFactory a = 370 b = 420 c = 2 model =…
Ken
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How do you install glpk-solver along with pyomo in Winpython

I want to use "pyomo" for my studies. I installed pyomo via easy_install coopr install instructions, Pyomo needs a solver to work so I wanted to install the (GNU Linear Programming Kit) glpk_webpage, pyomo seems to be installed just right because I…
www.pieronigro.de
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How you enable CBC to return best solution when timelimit? (Pyomo)

I am trying to use CBC(v2.10.3) on Pyomo to solve for a integer linear problem. When executing the solver, I am currently setting a timelimit of 600s. opt = SolverFactory ("cbc") opt.options['seconds'] =600 Within this timelimit, solver manages to…
tb_
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Does Pyomo support generation of multiple solutions?

I've been using Gurobi to solve an MILP problem, and Pyomo for generating the model. Gurobi supports returning a Solution pool, and I want to be able to generate multiple solutions using this pool. Is this supported in Pyomo? I've tried using…
Suhas Pai
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Finding out reason of Pyomo model infeasibility

I got a pyomo concrete model with lots of variables and constraints. Somehow, one of the variable inside my model violates one constraint, which makes my model infeasible: WARNING: Loading a SolverResults object with a warning status into…
oakca
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Pyomo cannot find GLPK solver on Docker machine

I have a Docker machine running Linux. I am using Pyomo with the GLPK solver. I installed GLPK from the shell command line for the Docker image, using apt-get install glpk-utils I have all my code saved under the subfolder /code I can see glpsol is…
Ryan Skene
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Installing Pyomo on Windows with Anaconda (Python)

I would like to solve LP and ILP with Pyomo (Coopr) but unfortunately I am so newbie and I cannot run it properly. I have already installed Pyomo (Coopr) by following its instructions pip install Coopr I can import the module without problems: $…
FZNB
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How to extract Indexed Variable information in pyomo Model and build Pandas Dataframe

I am attempting to solve a MIP using Pyomo with several Indexed Variables of different sizes. What I would like to do is export the results of the variables to a dataframe so that I can further analyze these results. My problem is that I cannot…
Corey Duncan
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Defining specific set of values for 2 variables in PYOMO

I am trying to assign material property using multiple variables. For example; density and conductivity are two decision variables for material_1, material_2 and material_3. I have to input the following information: density of material_1 =…
Rua Goa
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Pyomo - Objective function as average value of param

I am trying to use Pyomo for an LP problem and I would like the objective function to be the mean value of a particular parameter in my dataframe (which I'll call obj_param). I had previously set this up like so: model =…
seth127
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