Re: [Help-glpk] Indexing a subset from 1..n

[joel mortyn]

Thank you so much. That worked a treat.

> Date: Tue, 27 Nov 2012 22:53:20 +0100
> From: address@hidden
> Subject: Re: [Help-glpk] Indexing a subset from 1..n
> To: address@hidden; address@hidden
>
> Hello Joel,
>
> param nPeriods := 12;
> set Periods, default{1.. nPeriods};
> # let even period be open
> param FacilityOpen{p in Periods}, binary := if p mod 2 == 0 then 1 else 0;
> set OpenPeriods:= setof{p in Periods: FacilityOpen[p] = 1}(p);
> param nOpen := card(OpenPeriods);
> set NOpen := {1..nOpen};
> # beware this will take n^2 time
> param pOpen{n in NOpen} := sum{p in OpenPeriods :
> n ==card(setof{i in OpenPeriods: i <=p }i) } p;
> display pOpen;
> end;
>
> Best regards
>
> Xypron
> -------- Original-Nachricht --------
> > Datum: Wed, 28 Nov 2012 08:15:46 +1100
> > Betreff: [Help-glpk] Indexing a subset from 1..n
>
> > Hello all,
> > I have a set of Periods from which I create the subset OpenPeriods when
> > the facility is open.
> > param nPeriods;set Periods, default{1.. nPeriods};param FacilityOpen{p in
> > Periods}, binary;set OpenPeriods:= setof{p in Periods: FacilityOpen[p] = 1}
> > (p);
> > The facility is not open during all periods and I have a constraint that
> > considers the configuration of the facility the previous time it was open.
> > So I am trying to index the set of OpenPeriods from 1...card(OpenPeriods)
> > rather than with p but so far without any luck.
> > Any help would be much appreciated.
> > Thanks,
> > Joel