Hi Andrew, Thanks for your reply. Yes, I know the latest version is 4.32. But since version 4.8 has Java API provided by Bjoern (http://bjoern.dapnet.de/glpk/index.htm), my Java programs used the API.
I tried other coefficients. It turns out for larger values, I got strange results as well. This may be because I'm trying to solve feasibility problem, so I modified my subject a bit. Below is an example of the feasibility problem (I don't need objective function. In my implementation, I use a fake objective function z = x1 + x2): The LP is as follows: Maximize z = x1 + x2 0.04600662731785218 x1 - 1 x2 <= 0 0.0036805289240121435 x1 - 1 x2 <= 0 0.08833272571169222 x1 - 1 x2 <= 0 x1 + x2 = 1 We can see that (x1 = 0, x2 =1) is a feasible solution. The glpk tells me that the problem is feasible, but the values of x1 and x2 are both 0, which contradicts with my constraint x1 + x2 = 1. I figured that if I change my problem to the follows, glpk works. Maximize z = x1 + x2 0.04600662731785218 x1 <= 0 0.0036805289240121435 x1 <= 0 0.08833272571169222 x1 <= 0 x1 + x2 = 1 glpk tells me that: (x1 = 0, x2 =1) is a feasible solution. This is what I expected. Can you explain why glpk gives me strange results in the first problem? Thank you very much! Yao _______________________________________________ Help-glpk mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-glpk
