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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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Linear programming - dual simplex variable meanings?

I have just learned the simplex method for solving linear programs, and I'm trying to understand what it's dual problem represents. I understand the mechanics of solving a dual problem - I do not need help with that. What I can't get (even after…
penelope
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C/C++ implementation of simplex method

I am unable to find an implemenation of simplex method.I have a set of points and want to minimize theie distance so i only need the method simplex I have google before posting this question and could nt find anything that I could use
abas
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Hello World example for SimplexSolver

I am trying to solve a optimization problem using Apache Commons. I found a "Hello World" example here for Commons Math 2. But, I would like to use Commons Math 3.2 and I couldn't find any example on how to use this part of the code: PointValuePair…
Esther
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How to determine simplex time complexity (ie Max flow)

Simplex algorithm is said to have exponential worst case time complexity. Yet it is still often used in practice. How can you determine the average time complexity for a certain problem (being solved with simplex). For example, what is the average…
Ben
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Choosing the initial simplex in the Nelder-Mead optimization algorithm

What's the best way to initialize a simplex for use in a Nelder-Mead simplex search from a user's 'guess' vertex?
craigB
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Has anyone seen a simplex library for javascript/nodejs

I've been writing a lot of my scripts in NodeJs, but I need to use something like the GLPK libraries in order to handle some of the optimizations in my scripts. Has anyone heard of a javascript driver? I wonder how hard it would be to port coin to…
BHP
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zmq: can multiple threads PUSH in a simple PUSH-PULL pattern

I have two processes: a producer which pushes messages via ZMQ to a consumer in a simple PULL-PUSH point-to-point pattern. The producer has several internal threads that send() via zmq. However, 0MQ's docs suggest not to share sockets between…
Jonathan
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Generating tile noise maps "on the fly"

I’m interested in generating 3D height maps for a 2D game I am working on. I am using this to create land masses like in Minecraft or Dwarf Fortress and have done this before but only in fixed…
Jay_PC
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How to find the smallest N dimensional simplex from a set of points that contains a given point?

I've looked all over google and stack but haven't found an answer to this problem yet. I keep finding results relating to the simplex method or results for finding the smallest arbitrary simplex (i.e. the vertices are not constrained). Neither can I…
gibbled
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How to visualize simplex?

Let's say I have n-simplex and a grid on it. For every point of the grid I evaluate a function. But I truly don't know how to visalize the data received by this evaluation. Would you help me with any approach to represent a simplex in 3-D or 2-D,…
Macaronnos
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How to set decision variables types like binary, int, double in Apache Commons Math SimplexSolver?

How to set decision variables types like binary, int, double in Apache Commons Math SimplexSolver? The output of the program below is this: 332.6666666666667 1.0 8331.666666666668 I want decision variables to be of type int not double; output…
user1020082
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Python linprog minimization error - simplex method

I'm using scipy.optimize.linprog library to calculate the minimization using the simplex method. I have two cases where I am getting error: "ValueError: Phase 1 of the simplex method failed to find a feasible solution. The pseudo-objective function…
Dubster
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Nelder Mead algorithm for constrained optimization?

I have read that Nelder Mead algorithm is working for unconstrained optimization. http://www.scholarpedia.org/article/Nelder-Mead_algorithm I think in Matlab Nelder Mead is used also for unconstrained optimization. However, I am a little bit…
Sorin
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Scipy fmin with integer solution

I need to minimize a function that only allows integer input. Can I solve it with scipy.optimize.fmin? Otherwise, is there any alternative?
Jorge Barata
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NumPy vs SymPy Row operations different?

I cannot understand for the life of me why a row operation with NumPy just clearly leads to the wrong answer. The correct answer is in the SymPy matrix. Can anyone tell me why NumPy is unable to perform the correct calculation? I'm going crazy.…
James Salafatinos
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