Re: Linear Program Optimal Extreme Points
Manuel Muñoz Márquez <[email protected]> Fri, 07 Oct 2022 09:49:13 +0200
| Newsgroups | gmane.comp.gnu.glpk |
|---|---|
| Message-ID | <[email protected]> |
Hi, El vie, 07-10-2022 a las 11:04 +1030, Prabhu Manyem escribi=C3=B3: > To Andrew, Peter and Manuel, >=20 > Thank you for your help on this topic. >=20 > To Manuel, Why only vertices next to the starting vertex?=C2=A0 If the > links are A-->B-->C and B-->D, so first you go from A to B, then B to > C, then backtrack to B (from C), and then you can go from B to D... > This is what I had in mind when I said "traverse in a tree-like > fashion".. (But yes, to do backtracking, you should store the Bases of > A and B in memory). You are wright, I miss the second and successive iteration. My first impression is that the procedure you propose is not the same as th= e one in the book. But from the practical view point I think the problem will be intractable v= ery soon. Regards, Manuel >=20 > But in the example that you gave, I can walk directly from BR (bottom > right) to TR (top right), or from TL to TR. >=20 > To Peter-- Yes, they can have exponentially many vertices.. But I > think there are "doubly polynomial" algorithms that can do > enumeration.. Doubly Polynomial means, polynomial in the size of the > input+output.. Here is one reference: > https://www.research-collection.ethz.ch/handle/20.500.11850/426218 > (Chapter 8, I think).. I came to know about this only recently. >=20 > Best, > -Prabhu >=20