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### Two phase method in linear programming

suppose following tableau came after one iterations in first phase of a two phase method problem, here $s_1$ is a surplus variable and $s_2$ is a slack variable $w$ is a artificial variable. i tried ...
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### How to configure simplex method to start from a specific point

If I have a linear programming problem e.g. $$\max 2x_1 + x_2$$ with these constraints $$x_1-2x_2 \leq 14$$ $$2x_1-x_2\leq 10$$ $$x_1-x_2 \leq 3$$ And I want to solve the problem starting from a ...
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### Canonical form simplex method

In 2-phases simplex method what kind of operations must be done to get the canonical form tableau? In this step(phase 2 of 2-phases method) after the remotion of artificial variables columns of ...
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### Matrix of LP has not full rank after converison to standard form

I have coded a reader for MPS files in MatLab, which yields A, b and c as in ...
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### General question about new objective function W using the simplex method

In regards to the two-phase simplex method; When creating a new objective function that consists the sum of the constraint(s) with artificial variables, I am told that if the Min value of (wmin) w is >...
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### How to terminate Phase-I in case of infeasible solution.

I'm unable to understand the following in case of a two phase method : We terminate the phase-1 and start with phase-2 of two phase method when all artificial variables are driven to zero . but ...
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### Two-phase simplex method to solve minimise problem

Using the two-phase simplex method I am asked to Minimise: z= 3x2-x3+8 Subject to: x1+x2+x3=10, 2x1+3x2+x3=15 x1,x2,x3>=0 I am not sure how to go about this ...
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### How to Adequately Implement Phase I of Two-Phase Simplex Algorithm on a Computer with Floating Point Error

I'm currently trying to write some code that implements Phase I of the two-phase Simplex Algorithm described here: http://www.statslab.cam.ac.uk/~ff271/teaching/opt/notes/notes8.pdf In order to test ...
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### Expressing problems in canonical form for solving with simplex

The Picnic Hamper Company has a store containing 10,000kg of nuts, 4000 packs of smoked salmon, 2000 bottles of wine and 1500 Victoria sponges. It intends to use these goods to make up three different ...
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### How does the two phase method for linear programs work…

I understand that by adding artificial variables the problem can be reformulated as a new problem where the "starting point" is readily found. What I don't get is how when this extended problem is ...
I cannot understand the line -12, -4, -5, 1, 1, -1, 0, 0, 0. Now the formula $\bf c - \bf A ^t \bf y$ when $c=0$ will result into the line. It is just many times a ...