[Coin-discuss] Controlling printing for CbcStrategyDefault

[Kish Shen]

John,

Thank you very much for your reply.

On Friday 07 July 2006 16:48, John J Forrest wrote:
> Kish,
>
> You can derive from CbcStrategyDefault and do what you want but it seems a
> sensible think to change the default to pass in the CbcModel's handler. So
> I will change.
>
> Until I do - add
>
> process->passInMessageHandler(model.messageHandler());
>
> just after process is created (line 300 of CbcStrategy.cpp)
>
> and tell me if that works.
>
I have made this change, and it works -- the output of process is now properly 
handled.

One question about this preprocessing: do you expect it to improve the 
performance? In my case, I have already called CglPreprocess on the problem 
when it was first copied from the OsiClpSolver to the CbcModel, and in the 
rather limited test examples I have been running (mainly used to test if my 
changes are working, rather than for measuring performances), where some 
MIPLIB problems are solved (but they are modelled in our ECLiPSe programming 
language, rather than read in from an MPS file), doing this second 
preprocessing in CbcStrategy does not improve the solving times, and in fact 
for one problem (noswot), it slows the solving time time from 33s to 54s. 

> Your other point about infeasible solutions is more complicated and I will
> put the changes into the development branch.
>
> John Forrest
>

I didn't know that you divide your development into different branches -- does 
this mean that the branch where you do the bug fix is the patch branch? 
How is the development branch released?

A related question I have had is: do the various COIN components have version 
numbers? It would be nice to be able to refer to a version number for say Clp 
or Cbc. 

Thanks and cheers,

Kish