[Clp] CLP and COIN parameters/ was corrections to coinmp

[Rod Frowd]

Larry:

You are correct about the scaling parameter.

When I started this I was using the pre-built dll and after some more 
testing it seems that most of these parameter changes are unnecessary 
when using the dll built from the latest source. As far as I can tell 
the prebuilt dll was built 2-3 years ago and it seems that there have 
been many changes to the baseline code since then.

The only parameter change that seem to make a difference to the problem 
I am solving with the dll built from latest source is the perturbation 
parameter.

Rod


Larry A. Taylor wrote:
> At 05:51 PM 2/18/2008, Rod Frowd wrote:
>> Parameters I changed were:
>>
>> COIN_INT_SCALING  set to 5 was 3
>> COIN_INT_PERTURBATION    set to 50 was 100
>> COIN_INT_PRIMALPIVOTALG  set to 4 was 1
>> COIN_INT_DUALPIVOTALG    set to 3 was 1
>>
>> It went from 15000 iterations to around 5000 with these changed. The 
>> problem I am solving is not well conditioned numerically so these 
>> parameters seem to help.
>> ...
>> Rod
>
> I have been looking at various places in the code, and I thought that 
> the only
> options to COIN_INT_SCALING  were 0,1,2,3 and 4.
>
> For instance, in CoinMP.cpp, the options table has these lines:
>>           "Scaling" ,                              "Scaling" ,      
>> GRP_SIMPLEX,        3,        3,      0,       4,  OPT_LIST,   0,   
>> COIN_INT_SCALING,
>>       /* Sets or unsets scaling, 0 -off, 1 equilibrium, 2 geometric, 
>> 3, auto, 4 dynamic(later) */
>
> ... and there is a similar comment in Clp_C_Interface.cpp.
>
> So where is option 5 documented, and what does it do?
>
> LAT
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