[Coin-lpsolver] problems with BInvCol and BInvRow

[Anureet Saxena]

hi,

There seems to be some trouble with the 
OsiSimplexInterface::getBInvCol() and
OsiSimplexInterface::getBInvRow() functions.

In particular, constructing the basis inverse via these two functions gives
different results (after transposing). Furthermore, the problem is specifically
in those rows whose corresponding basic variable is a slack variable. 

A small example (3 rows and 5 variables) and relevent code can be downloaded
from the following link:

http://www.andrew.cmu.edu/user/anureets/tmp/
File Name: BInvCol_case.tgz

It will be very nice if someone could point out and/or rectify the error.
 
On a different note, OsiSimplexInterface has a function:
 
enableSimplexInterface(bool doingPrimal).
 
The role of the parameter "doingPrimal" is not adequately described in the doxygen documentation. Could someone please give some idea as to what this parameter accomplishes. 


regards,
Anureet Saxena
ACO Doctoral Student,
Tepper School of Business,
Carnegie Mellon University.





Anureet Saxena
 anureet at cmu.edu
 anureet at yahoo.com
 
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