[Help-glpk] Patches to improve pseudocost initialisatiion speed

[Chris Matrakidis]

Andrew,

Since you are preparing a new GLPK release, I'm sending you three
patches to consider, that improve the speed of pseudocost
initialization.
The first reuses the same glp_prob in each round to avoid unnecessary
copying, the second introduces a bfd_copy function and the third uses
bfd_copy to avoid recalculating the exact same factorisation in every
simplex call during each initialisation round.
These patches do not affect the execution order of the code, only the
initialisation speed: in all tests I did, I get the exact same number
of nodes and simplex iterations

Best Regards,

Chris Matrakidis

pcost1.patch
Description: Text Data

pcost2.patch
Description: Text Data

pcost3.patch
Description: Text Data