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Questions tagged [simplex]

A simplex is a generalization of the notion of a triangle or tetrahedron to arbitrary dimension.

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Simplex solver in Z3

I'm aware that there is a simplex solver implemented in z3. Is it possible to use the solver for linear optimization? Where is the interface for the solver located in the z3 source code?
liyistc
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simplexml_load_string foreach doesnt display anything

My PHP code looks like below, it shows blank i want to Display all the records with hyperlinks like $Name where $Id, $Name is from XML feed $path = 'www.abc.com/test.xml'; $ch = curl_init(); curl_setopt($ch,…
user580950
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Table Simplex method: 1) why do we need to have identity matrix? 2) Nonexistance of optimal solution 3) Stop iteration condition

Recently I have read this superb Simplex method tutorial: http://www.tutor.ms.unimelb.edu.au/simplex_intro/index.html . While explaning things in very clear fashion, some obscurity still left. From here you may read (identity matrix): So, what is…
Vadim
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Lua - Filter Forge - Simplex Noise: Need help troubleshooting 'attempt to index a nil value (local 'grd')'

I'll get the ball rolling with this: I converted Simplex noise written in java to lua and found myself caught on a potential out of bounds error being reported as an attempt to index a nil value. I've commented out most of the code and focused on…
DavidBryanRoberson
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How does Bowyer-Watson algorithm for Delaunay triangulation run in O(n^2) but runs over all the simplexes?

The Bowyer-Watson algorithm for Delaunay triangulation is known to run in O(n^2) according to the authors, where n is the number of data points in R^d. In addition, the algorithm (for example, as is written in Bowyer's paper, at stage 5 of the…
Joe Doe
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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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How could constraints be dynamiclly defined with simplex method?

I try to correctly write a linear programming model for my problem. I want to minimize the sum of w_i and i have the following constraint: (a_i+w_i ≤ w_j) XOR (a_j+w_j ≤ w_i) a_i and a_j are integer constants w_i and w_j are integer variables in…
FifaBen
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What is the accuracy of the CLP solver (Coin-Or)?

I am trying to compare LP solvers to see wheter I can use them for my problem. In ding so I need an accurate solver. What I could find are tolerances, though I am not sure whether this is a proper indicator. For GUROBI the integrality tolerance is…
simon
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How to avoid Delaunay.find_simplex function from returning -1

I have a set of 500 7D array of points. When I run the below code: from scipy.spatial import Delaunay delau = Delaunay(ip) Delaunay.find_simplex(delau,ip) Delaunay.find_simplex returns -1 for only one data point out of 500. I understand that this…
Pragati
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Simplex Algorithm - Worst Case

Its given that worst case time complexity of simplex algorithm is O(2^n). What is the worst case in simplex algorithm? To calculate time complexity I want to know about the worst case.
Anupama Karunarathna
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CVRP without visiting each node

I have a linear model for a capacity vehicle routing model. Now I want to put in a constraint on the maximum number of active edges which will result in the fact that not each node can be visited. However each route should start and end at the depot…
Marty
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Finding optimal solution to multivariable function with non-negligible solution time?

So I have this issue where I have to find the best distribution that, when passed through a function, matches a known surface. I have written a script that creates the distribution given some parameters and spits out a metric that compares the given…
Fred E
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simplex - algebraic intuition behind the basis of the canoncial form

I'm trying to understand the simplex iteration of a problem with n variables and m technological constraints by following this text. I understand well the geometric interpretation of the iteration - moving between adjacent vertices. However, I fail…
ihadanny
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why I get huge number in converting V-reresentation to H-representation in sage?

I have a set of vertices and I want to find a H-representation of them. I used sage to do that but I got weird number in the inequalities! here is my code: vert2 =…
sherek_66
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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…
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