Hi, in a simple problem I am getting "Dual infeasible due to empty column 'theta.10'." Yet, when I check for this column using "linear_constraints.get_coefficients", right before solving, I can clearly see that the column has several ones.
Where might be my error?
Many thanks,
Alvaro
Topic
This topic has been locked.
2 replies
Latest Post
 20130205T17:58:01Z by alvarolorca
ACCEPTED ANSWER
Pinned topic Problem with "Dual infeasible due to empty column"
20130205T15:58:18Z

Answered question
This question has been answered.
Unanswered question
This question has not been answered yet.
Updated on 20130205T17:58:01Z at 20130205T17:58:01Z by alvarolorca

ACCEPTED ANSWER
Re: Problem with "Dual infeasible due to empty column"
20130205T16:32:15Z in response to alvarolorcaThe column may be empty after presolve. What happens if you disable presolve (set CPX_PARAM_PREIND to 0)? 
ACCEPTED ANSWER
Re: Problem with "Dual infeasible due to empty column"
20130205T17:58:01Z in response to alvarolorcaThat solved it, thank you Daniel.
I think the message is confusing, it would be nice if it specified that a reduction of the problem had an infeasible dual (but it is really great how fast you answered with the right approach).
Alvaro