j2kun / simplex-algorithm

Python source code for Linear Programming and the Simplex Algorithm

simplex-algorithm

Python source code for Linear Programming and the Simplex Algorithm

simplex-algorithm's Issues

Degeneracy detection does not work

Unfortunately, I am not 100% sure (yet) how the degeneracy test is supposed to work but it cannot work in it's current form. The heapq.nsmallest function returns two tuples that always have two different first elements. Hope I am not missing something. :)

Incorrect algorithm

I think this algorithm doesn't work properly. For example, for this data:

F = 300x1 + 250x2 + 450x3 --> max
15x1 + 20x2 + 25x3 <= 1200
35x1 + 60x2 + 60x3 <= 3000
20x1 + 30x2 + 25x3 <= 1500
250*x2 >= 500
x >= 0

Returns: [(0, 12.0), (2, 180.0), (4, 60.0)], 23400.0

But the answer should be:
F = 23060
x1 = 56, x2 = 2, x3 = 12.8

Also, I've checked some other data. And for this data, it doesn't work at all.