[Couenne] Couenne error with final solution

[Akshay Gupte]

Hi,

I am attaching a sample output below:


Cbc0013I At root node, 1 cuts changed objective from -37772.749 to 
-37772.688 in 2 passes
Cbc0014I Cut generator 0 (Couenne convexifier cuts) - 1 row cuts average 
2.0 elements, 320 column cuts (321 active)
Cbc0010I After 0 nodes, 0 on tree, 1e+50 best solution, best possible 
-37772.688 (777.18 seconds)
Cbc0010I After 100 nodes, 44 on tree, 1e+50 best solution, best possible 
-37739.148 (819.40 seconds)
Cbc0010I After 200 nodes, 93 on tree, 1e+50 best solution, best possible 
-37724.941 (835.35 seconds)
Cbc0020I Exiting on maximum time
Cbc0005I Partial search - best objective 1e+50 (best possible 
-37724.941), took 23515 iterations and 255 nodes (838.10 seconds)
Cbc0035I Maximum depth 80, 0 variables fixed on reduced cost
         "Not finished"
Stats: /tmp/at2730.nl   233 [var]    0 [int]  592 [con]  823 [aux]   
1595 [root]     1595 [tot] 0.008999 [sep]  838.775 [time]  838.782 
[bb]        -3.772494e+04 [lower]        -3.562291e+04 [upper]     255 
[nodes]

couenne: Optimization interupted on limit.

In the "Stats" line, a finite upper bound is being reported. However, 
just before exiting on maximum time, the "best solution" is +Inf.
The reported lower bounds are consistent in the two lines.

What is going on here ?

-- 
Regards,
Akshay

--
Akshay Gupte
Ph.D. student, Operations Research
School of Industrial&  Systems Engineering
Georgia Institute of Technology
Email: akshayg at gatech.edu

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.coin-or.org/pipermail/couenne/attachments/20120404/42e66ce2/attachment.html>