Date: Thu, 15 Dec 2005 19:01:48 -0800
Reply-To: NZOR <dwoodsnz@GMAIL.COM>
Sender: "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From: NZOR <dwoodsnz@GMAIL.COM>
Organization: http://groups.google.com
Subject: Re: Help with PROC LP, integer program initial solution
In-Reply-To: <BAY103-F6116A26A3619D013CA40BB03A0@phx.gbl>
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Thanks for the tips. The problem is IP, with some integer and some
binary variables. I'm not familiar with the term "driving
coefficients", I've been using the BINARY and INTEGER types of row to
specify the variables.
The _ORLP_ macro variable isn't telling me anything interesting.
I've tried using the PRIMALIN method, but I'm having trouble putting my
initial solution into the right format, if anyone has any tricks on
that let me know. It's years since I've done any math programming, so
trying to find which variables are basic and which are just at their
upper bound is beyond me. I tried creating a new problem which set all
the variables to their values in the optimal solution, and using the
PRIMALOUT from that as a PRIMALIN to a modified problem where the new
constraint is not binding, but it just told me that the basis in the
PRIMALIN data set is singular! Not quite sure why that is or what it
means.
I'd really prefer to use the BASIC type if I could get that working...
it seems to be the option designed for this purpose.
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