Originally posted by: stevenluda

Hi, all,

Is there a way to print out the columns of nonzero variables(in IP model)? I went through historical posts, it was mentioned (e.g. in this post https://www.ibm.com/developerworks/forums/thread.jspa?messageID=14462382&#14462382) that the only way is to use iterator to go through all constraints to get the coefficients. However, it requires variables to be assigned names when building the model. Am I understanding right? What if the variables are not assigned names (e.g. in cutstock.cpp from the cplex distribution)? Is there a way to retrieve columns in this case?

Thanks
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: SystemAdmin

You can use the code in the quoted post and replace getName() by getId().
Each variable and each range in Concert has a unique id which is returned by IloExtractable::getId() (IloExtractable is a super class of IloNumVar and IloRange).
#CPLEXOptimizers
#DecisionOptimization

Originally posted by: stevenluda

Great. Thank you for the help.
#CPLEXOptimizers
#DecisionOptimization