[FlopCpp] Question on indexing constraints

[Michal Kaut]

Hello,

sorry for the flood of emails, but I believe that it is better to keep 
different questions in separate emails.

I have been struggling to understand the indexing of FlopC++ constraints 
and must admit I still do not understand it properly. What confuses me 
most is that for each type of constraints I wanted to test, I was able 
to find several "seemingly equivalent" formulations, all of which 
compile, but only one of which gives the expected results.

I have tried to demonstrate it on the attached example, where the 
constraints with a name differing only in number are supposed to do the 
same thing, but only those that have "WORKS" in the comment actually 
generate the expected result. (I should probably confess that I am an 
AMPL user, so I have probably different understanding what an "index" 
means, compared to the GAMS-influenced designers of FlopC++.)
- Could someone try to explain to me why the bad formulations do not 
work, i.e. what they actually do? (They do something, as they compile.)
- Note that the example is only to illustrate indexing, the resulting 
model is not supposed to make any sense.


In addition, I was rather disappointed by the compilation speed (i.e. 
the lack of it): this very small example takes over a minute to compile 
on mu 3GHz Pentium 4 machine with gcc 3.4.5 (mingw on WinXP).
Of this time, 39 seconds are spend on the last three sets of constraints 
(getIndx1-3), i.e. the compile+link time is 26 seconds without those 
constraints. Is this normal/expected behaviour?
(Another interesting thing is that adding each of the three sets of 
constraints individually adds 5s, 10s and 10s respectively, i.e. 25 
seconds in total, while adding all three adds 39 seconds to the 
compilation time...)


And one more question: is it possible to get rid of the "eval subsetref" 
messages? Even with this small example, I get hundreds of them and 
setting model.silent() does not switch them off...


Thanks a lot in advance.

Regards,
Michal Kaut