968 questions
0 votes
0 answers
95 views
Microsoft Solver Foundation giving wild result for a simple problem
I'm using Microsoft Solver Foundation to minimize chi-square between two distributions. Usually there are multiple peaks in each distribution but occasionally there is just one. I'm noticing in that ...
4 votes
1 answer
101 views
Finding optimal placement of a 3D object in a partly filled 3D cage [closed]
I am searching for a good optimization technique/algorithm for placing a somewhat arbitrary 3D shape in a cage already filled with 3D shapes. These 3D shapes will primarily be regular cardboard boxes, ...
-1 votes
3 answers
103 views
SciPy fails to stably determine parameters given large data scale differences
We are using scipy.optimize.curve_fit to fit parameters X_eff and Y_eff for an Automated Market Maker (AMM) model: y_out = (Y_eff * x_in) / (X_eff + x_in) We're observing extreme sensitivity in the ...
0 votes
1 answer
60 views
Ceres solver: how to get history of solutions (found iteratively during the solve)?
In ceres solver, how to get history of solutions (found iteratively during the solve)? I start from the simplest hello world example: ceres-solver$ git remote -v origin https://github.com/ceres-...
0 votes
2 answers
134 views
New(ish) to Pyomo - How Do I Structure This Model? [closed]
I'm relatively new to both Python and Pyomo. I'm building an optimization script as one of my first projects. ChatGPT is hallucinating and I cannot find an example of how to properly set up the model ...
3 votes
0 answers
57 views
How to use the cold-start options with GEKKO correctly?
I was testing some options with Gekko for an optimization with MINLP , but I still couldn't figure out how the option COLDSTART = 2 work. Using the variable values from a prior solution as initial ...
0 votes
1 answer
106 views
How do I interpret scipy.optimize.minimize convergence metrics? Specifically, nit, nfev, njev in the output
I am solving an constrained, nonlinear optimization problem with scipy.optimize.minimize using the SLSQP solver. The optimization converges properly, but I want to have a better understanding of how ...
0 votes
1 answer
66 views
Satellite Orbit Raising Trajectory Optimization
I am trying to get an optimal solution for a trajectory optimization problem for a satellite orbit raising. My main objective is to minimize fuel. I have written a code as given below import casadi as ...
1 vote
2 answers
88 views
Is there any benefit of choosing to formulate constraints in a way or another in GEKKO?
I have an MINLP problem and let's say the continuous variable Q can only be 0 when the binary variable z is 0. Two ways to formulate this would be: m.Equation(Q*(1-z) == 0) (1) or m.Equation(Q < z*...
0 votes
2 answers
89 views
Maximizing correct classification with PuLP
In python, I’m trying to solve a problem of linear optimization with the pulp package. I have N continuous indicators and a dichotomous target. I need to select a subset of at most M indicators and a ...
0 votes
0 answers
35 views
Adding criteria to objective function does not change the solution
I have a MINLP problem that could be described with the following: a decision matrix NxM with binary variables a weight matrix T sized NxM the main criteria is to maximize sum of selected weights (...
0 votes
0 answers
54 views
Struggling to Configure Solvers for MINLP Optimization with Pyomo (using NEOS or Local Installation)
I'm working on a Mixed-Integer Nonlinear Programming (MINLP) optimization problem using Pyomo in Python, but I'm having trouble installing and configuring solvers. I've tried both installing solvers ...
3 votes
1 answer
66 views
Gekko using APOPT isn't optimizing a single linear equation represented as a PWL
I've run into an issue where I can't get APOPT to optimize an unconstrained single piecewise linear, and it's really throwing me for a loop. I feel like there's something I'm not understanding about ...
2 votes
1 answer
154 views
Maximum number of function evaluations has been exceeded - increase MaxFunEvals option
I was trying to fit a data set into a sinusoidal function with the code below: data = importdata('analisipicco.txt') ; x = data(:,1) ; y = data(:,2) ; yu = max(y); yl = min(y); yr = (yu-yl); ...
3 votes
1 answer
100 views
IPOPT solution by Gekko in comparison to GRG algorithm used within the Excel-Solver
The aim is to compute the thermodynamically equilibrated composition of the mixture at 1000K based on Gibbs' energy of formation of the reaction products and educts (steam+C2H6 in a molar ratio of 4:1)...