[Symphony] solution statistics

[Ashutosh Mahajan]

On Sat, 17 Jan 2009, S R wrote:

> I have developed a custom application to evaluate heuristics for
> generating problem specific cuts for an IP.  I'd like a couple of
> solution statistics, but it is not clear to me how to determine them.
> Can someone tell me how to determine:
> 
> 1. the best LP relaxation solution BEFORE cuts are generated.
> 

this is not displayed as part of default output in the current release. It is
however shown in the output in the stable version of symphony. so if you are
using stable or the trunk, then you should see lines like:

Solving...

solving root lp relaxation
The LP value is: 16.433 [0,128]

If you want to stick to the current release, then you will have to increase
verbosity to 4 or change the source code yourself. 

> 2. the best solution AFTER all cuts (both user and symphony) have been
> applied but before branch and bound starts.
> 

this is part of the default output. it should show something like:
Lower Bound in Root:            19.500

--
regards
Ashutosh Mahajan
http://coral.ie.lehigh.edu/~asm4