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Operations Research Models and Methods / Methods / Network Methods /
Teach Transportation Add-in

Change the Basis

The New Basis

The basis is changed by marking the entering cell with a B and marking the leaving cell with an N. The cell flows, dual variables and reduced costs are recomputed and shown on the image. It is should be noted that the reduced costs are determined by formulas in the worksheet cells. These formulas must not be disturbed for proper option of the program.

The cell flows and dual variables are computed and placed in the appropriate cell of the worksheet. These numbers may be changed by the student, but they will be replaced by the computer when the iteration button is clicked.

The complete set of iterations is shown on the next page. We show below the optimum solution.

The Optimum Solution

The process continues for some number of iterations. For the example, eleven iterations were required to obtain the optimum that is shown on the image. We know that it is optimum because all the reduced costs are nonnegative.

A restart button is provided on the worksheet after the optimum is found so the student can run the same problem with perhaps a different operating option.


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Operations Research Models and Methods
by Paul A. Jensen and Jon Bard, University of Texas, Copyright by the Authors