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Questions tagged [simplex-algorithm]

43 questions
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linear optimization with scipy / simplex do not deliver optimum

I am trying to solve the problem described by Saul Grass in his book "Illustrated Guide to Linear Programming", page 12ff The transportation problem. Refrigerators have to be delivered to 3 stores (S1,S2,S3) in the following quantities…
F Massion
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Solve optimization with binary variables

I'm trying to optimize the following: people (column id) should go to one of the points A:G. Let's say that exactly two people (from a group of 14) must go to one of the 7 locations. I want to minimize the sum of the distances covered. id <- 1:14 A …
Marcelo Rodrigues
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How do you estimate the parameter error/uncertainties using the Nelder-Mead method in scipy.optimize.minimize using the final_simplex in the output

I am trying to estimate the error/uncertainties in the estimation of the power-law fitting parameters (m, n, b) of the form y = m(x-b)^n, which I fitted to a dataset. When I use the Nelder-Mead method from scipy.optimize.minimize I get a final…
nebula1
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Nelder-Mead initial simplex size

I use Matlab's fminsearch function for finding the minimum with Nelder-Mead. fminsearch calculates the size of the initial simplex automatically. In my case, the initial simplex is too small, thus it performs not well. fminsearch uses a leg of…
machinery
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How to handle the special cases of simplex algorithm for linear programming

This is a follow-up question to the SO question: Code a linear programming exercise by hand . I have a similar interest in implementing the simplex algorithm (linear programming) for pedagogical purposes. I understand that there are many…
thor
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Solve a linear programming (LP) problem in R

The function takes in the coefficients of the objective function, the constraints matrix, the right-hand side values for the constraints, the direction of the constraints, and the type of the LP problem (minimization or maximization). It then uses…
proxyy
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2D fiber alignment using the simplex algorithm

I have been writing some code for automatically aligning my fiber (whose X, Y, Z positions are controlled by a motor) to a light source. For this I have written my axis.move_to(pos) method to move an axis to a position, and a pm.meas_power() method…
Enzo
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python network simplex algorithm for transportation problem?

After doing a lot of research I'm unable to find a network simplex algorithm for Python. This algorithm has been implemented in many other languages so there must be a python implementation I guess? I don't want to use PuLP as PuLP uses a standard…
learnPyt
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Simplex Algorithm: Initialize-Simplex

I am trying to figure out the simplex algorithm in the book "Introduction to Algorithms, 3rd edition". The procedure "Initial-Simplex" takes as input a standard form, and check if there is an initial basic feasible solution for the standard form.…
tjfy1992
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Implementing Simplex Method infinite loop

I am trying to implement a simplex algorithm following the rules I was given at my optimization course. The problem is min c'*x s.t. Ax = b x >= 0 All vectors are assumes to be columns, ' denotes the transpose. The algorithm should also…
campovski
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Linear programming with scipy.optimize.linprog returns Optimization failed

I am trying to use linprog in order to optimise the following problem (uploaded in Google Drive). The dataset itself is uploaded here So far I have the written the following implementation in Python: import pandas as pd import numpy as np df =…
Vasil Yordanov
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Solving LPP using Simplex Method with variables subject to a range

I am currently working on a problem which can be solved using linear programming according to the research I have done here, on YouTube and on other websites. I have familiarized myself with the so called Simplex Method and it’s variations, like –…
Dizarb
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Simplex algorithm in Excel without Solver

I am looking for an Excel table with formulas (no VBA, no Solver) that can solve LP problems: Ax=b 0<=x cx->min With Solver and VBA, I can do it but I would like a solution which builds only on Excel Formulas. Or a proof that no such system…
z32a7ul
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Pulling non zero values from excel

i have made this table in excel of items of food from a menu with their nutritional value. I've then got another table that has each item in one row and the quantity consumed of each item In the row below. I've then used the solver tool in excel to…
user123
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linear programming with dual simplex in R

I have a linear programming problem that I'm trying to solve in R. I have used lpSolve package. lpSolve by default uses primal simplex algorithm to obtain solution. What if I want to change the algorithm to dual simplex ? The results vary widely…
forecaster
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