[SCIP] Return value from SCIPgetVarRedcost does not match objective function value of pricer

[Hewitt, Michael]

I am using column generation to solve a network optimization problem and adding variables to the master via a custom pricer. 
After I discover the column to add in my pricer, my code
1) calls SCIPcreateVar (initial set to true) to create the variable for that column
2) Sets the appropriate coefficient of each constraint that variable should participate in 
	note that a) each constraint marked as modifiable when created and is the transformed constraint
3) calls SCIPaddPricedVar

Just to be certain, I then call SCIPgetVarRedcost to get the reduced cost of this variable and ensure it matches with what my pricer reports.
It often does not. 

Does this mean there is a problem? Or is it possible the dual variables when I call SCIPgetVarRedcost no longer reflect the current basis matrix?

Mike Hewitt
Professor 
Faculty Director, Supply Chain and Sustainability Center
Information Systems and Supply Chain Management
Quinlan School of Business
Loyola University Chicago
312-915-7394
mhewitt3 at luc.edu