Error 66 - the symbol shown has not been defined or assigned (for objective function)
Posted: Mon Apr 24, 2017 10:14 am
Hello,
I'm struggling with my code. It's a MILP problem for plant and capacity allocation with 210 binary and 5 continuous variables. When I run the code, it returns the error 66 "the symbol shown has not been defined or assigned" in relation to my objective function in the very last solve statement, but the objective function has been defined. Could you take a look at my code and advise what I could be doing wrong please? Thank you!
Agnessa
I'm struggling with my code. It's a MILP problem for plant and capacity allocation with 210 binary and 5 continuous variables. When I run the code, it returns the error 66 "the symbol shown has not been defined or assigned" in relation to my objective function in the very last solve statement, but the objective function has been defined. Could you take a look at my code and advise what I could be doing wrong please? Thank you!
Code: Select all
sets
i farms /
$call =xls2gms r=farms!B3:B39 i=parameters_for_model.xlsx o=seti.inc
$include seti.inc
/
j plastic /
$call =xls2gms r=plastic!B2:B6 i=parameters_for_model.xlsx o=setj.inc
$include setj.inc
/
p product /
$call =xls2gms r=product!B2:B6 i=parameters_for_model.xlsx o=setp.inc
$include setp.inc
/
l plant location /
$call =xls2gms r=distance_lc!B3:B7 i=parameters_for_model.xlsx o=setl.inc
$include setl.inc
/
c customer /
$call =xls2gms r=demand!B3:B7 i=parameters_for_model.xlsx o=setc.inc
$include setc.inc
/
m month /1*12/
;
scalars
int interest rate in % /0.08/
infl rate of inflation in % /0.007/
y investment lifetime in years /20/
Tcost transportation cost £ per tn per km /0.31/
Whcost cost of storing 1 tn of plastic £ per tn /1.4/
Wage yearly wage of an engineering technician £ per year /22257/
s share of investment returned as subsidies in % /0/
Pcost operating costs £ per tn /21.1/
main share of investment to be spent on maintenance in % /0.04/
;
parameters
Alab labour cost
Inv investments
Sub subsidies
Dinb(i,l) distance between a farm i and a plant l
Doutb(l,c) distance between plant l and customer c
Mpl(i,j) mass of plastic j generated by farm i
Spl(j,m) share of plastic j supplied by a farm in month m
Price(p) price of product p
Conv(p) conversion coefficient of plastic into product p
Cdisp(j) cost of disposing 1 tn of plastic of j
Tdisp(j) cost of transporting 1 tn of disposed plastic j from a farm
D(c,p) demand of customer c for product p
Toutb(p) cost of transporting 1 unit of product p
;
$call GDXXRW i=parameters_for_model.xlsx o=indata.gdx par=Dinb rng=distance_il!B2:G39 rdim=1 cdim=1 par=Doutb rng=distance_lc!B2:G7 rdim=1 cdim=1 par=Spl rng=seasonality!B2:N7 rdim=1 cdim=1 par=Mpl rng=farms!B2:G39 rdim=1 cdim=1 par=D rng=demand!B2:G7 rdim=1 cdim=1 par=Price rng=product!B2:C6 rdim=1 par=Toutb rng=product!B2:B6,D2:D6 rdim=1 par=Conv rng=product!B2:B6,E2:E6 rdim=1 par=Cdisp rng=plastic!B2:C6, rdim=1 par=Tdisp rng=plastic!B2:B6,D2:D6 rdim=1
$GDXIN indata.gdx
$Load Dinb, Doutb, Spl, Mpl, D, Price, Toutb, Conv, Tdisp, Cdisp
$GDXIN
display Conv, Tdisp, Toutb;
parameters
Ainb inbound transportation cost
Awh warehousing cost
Aop operating cost
Amain maintenance cost
Aoutb outbound transportation cost
Rprod revenues from products
Rdisp revenues from saving on plastic disposal (convenitional)
Df discounting coefficient
Pmon(l,m) monthly production - conversion of plastic in location l in month m
Sale(c,p) sales to customer c of product p
Staff(l) number of engineering technicians on the plant l
Whstock(m,l) amount of plastic left in the plant l at the end of month m
;
Df = [1-cvpower({1+(int-infl)/(1+infl)},(-y))]/(int-infl);
binary variables
Loc(i,l) existing link between the farm i and the plant l
Cloc(l,c) existing link between the plant l and the customer c
;
Positive variables
Cap(l) capacity of plant l to covernt plastic;
Variables
Z;
equations
Inv1, Staff1(l), WH1(l), WH3(l), WH4(l), WH5(l), WH6(l), WH7(l), WH8(l), WH9(l), WH10(l), WH11(l), WH12(l), WH2(l), Maint, Pmon1(l), Pmon2(l), Pmon3(l), Pmon4(l), Pmon5(l), Pmon6(l), Pmon7(l), Pmon8(l), Pmon9(l), Pmon10(l), Pmon11(l), Pmon12(l), Sales1(c,p), Ainb1, Awh2, Aop3, Aoutb4, Rprod5, Rdisp6, profit, Sub8, Alab9, Link(i), Linkup(l), Linklow(l), Capacity, MassbalanceS, MassbalanceP(p), MassbalanceD(p);
Inv1.. Inv =e= 1000*(sum(l, [(1.8*Cap(l)+2527)$({Cap(l)>1600} and {Cap(l)<25550})]) + sum(l, [(3.3*Cap(l)+96)$(Cap(l)<1600)]) + sum(l, [(1.2*Cap(l)+6893)$(Cap(l)>25550)]));
Staff1(l).. Staff(l)$(sum(i, Loc(i,l))>0) =e= 0.001*Cap(l)+2.44;
Maint.. Amain =e= Inv * main ;
Pmon1(l).. Pmon(l,"1") =e= (sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"1")])$((sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"1")])<Cap(l))+Cap(l)$((sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"1")])>Cap(l));
WH1(l).. Whstock("1",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"1"))-Pmon(l,"1");
Pmon2(l).. Pmon(l,"2") =e= Cap(l)$({Whstock("1",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"2")]}>Cap(l))+(Whstock("1",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"2")])$({(Whstock("1",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"2")])>(0.25*Cap(l))} and {(Whstock("1",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"2")])<Cap(l)});
WH2(l).. Whstock("2",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"2"))+Whstock("1",l)-Pmon(l,"2");
Pmon3(l).. Pmon(l,"3") =e= Cap(l)$({Whstock("2",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"3")]}>Cap(l))+(Whstock("2",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"3")])$({(Whstock("2",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"3")])>(0.25*Cap(l))} and {(Whstock("2",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"3")])<Cap(l)});
WH3(l).. Whstock("3",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"3"))+Whstock("2",l)-Pmon(l,"3");
Pmon4(l).. Pmon(l,"4") =e= Cap(l)$({Whstock("3",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"4")]}>Cap(l))+(Whstock("3",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"4")])$({(Whstock("3",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"4")])>(0.25*Cap(l))} and {(Whstock("3",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"4")])<Cap(l)});
WH4(l).. Whstock("4",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"4"))+Whstock("3",l)-Pmon(l,"4");
Pmon5(l).. Pmon(l,"5") =e= Cap(l)$({Whstock("4",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"5")]}>Cap(l))+(Whstock("4",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"5")])$({(Whstock("4",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"5")])>(0.25*Cap(l))} and {(Whstock("4",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"5")])<Cap(l)});
WH5(l).. Whstock("5",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"5"))+Whstock("4",l)-Pmon(l,"5");
Pmon6(l).. Pmon(l,"6") =e= Cap(l)$({Whstock("5",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"6")]}>Cap(l))+(Whstock("5",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"6")])$({(Whstock("5",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"6")])>(0.25*Cap(l))} and {(Whstock("5",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"6")])<Cap(l)});
WH6(l).. Whstock("6",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"6"))+Whstock("5",l)-Pmon(l,"6");
Pmon7(l).. Pmon(l,"7") =e= Cap(l)$({Whstock("6",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"7")]}>Cap(l))+(Whstock("6",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"7")])$({(Whstock("6",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"7")])>(0.25*Cap(l))} and {(Whstock("6",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"7")])<Cap(l)});
WH7(l).. Whstock("7",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"7"))+Whstock("6",l)-Pmon(l,"7");
Pmon8(l).. Pmon(l,"8") =e= Cap(l)$({Whstock("7",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"8")]}>Cap(l))+(Whstock("7",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"8")])$({(Whstock("7",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"8")])>(0.25*Cap(l))} and {(Whstock("7",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"8")])<Cap(l)});
WH8(l).. Whstock("8",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"8"))+Whstock("7",l)-Pmon(l,"8");
Pmon9(l).. Pmon(l,"9") =e= Cap(l)$({Whstock("8",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"9")]}>Cap(l))+(Whstock("8",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"9")])$({(Whstock("8",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"9")])>(0.25*Cap(l))} and {(Whstock("8",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"9")])<Cap(l)});
WH9(l).. Whstock("9",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"9"))+Whstock("8",l)-Pmon(l,"9");
Pmon10(l).. Pmon(l,"10") =e= Cap(l)$({Whstock("9",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"10")]}>Cap(l))+(Whstock("9",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"10")])$({(Whstock("9",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"10")])>(0.25*Cap(l))} and {(Whstock("9",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"10")])<Cap(l)});
WH10(l).. Whstock("10",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"10"))+Whstock("9",l)-Pmon(l,"10");
Pmon11(l).. Pmon(l,"11") =e= Cap(l)$({Whstock("10",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"11")]}>Cap(l))+(Whstock("10",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"11")])$({(Whstock("10",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"11")])>(0.25*Cap(l))} and {(Whstock("10",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"11")])<Cap(l)});
WH11(l).. Whstock("11",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"11"))+Whstock("10",l)-Pmon(l,"11");
Pmon12(l).. Pmon(l,"12") =e= Cap(l)$({Whstock("11",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"12")]}>Cap(l))+(Whstock("11",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"12")])$((Whstock("11",l)+sum[(i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"12")])<Cap(l));
WH12(l).. Whstock("12",l) =e= sum((i,j), Mpl(i,j)*Loc(i,l)*Spl(j,"12"))+Whstock("11",l)-Pmon(l,"12");
Sales1(c,p).. Sale(c,p) =e= sum((l,j,m),Pmon(l,m)*Conv(p)*Cloc(l,c))$((sum((l,j,m),Pmon(l,m)*Conv(p)*Cloc(l,c)))<D(c,p))+D(c,p)$((sum((l,j,m),Pmon(l,m)*Conv(p)*Cloc(l,c)))>D(c,p));
Ainb1.. Ainb =e= sum((j,i,l), Dinb(i,l)*Tcost*Mpl(i,j)*Loc(i,l));
Awh2.. Awh =e= WHcost*sum((m,l), Whstock(m,l));
Aop3.. Aop =e= Pcost*sum((l,j,m), Pmon(l,m));
Aoutb4.. Aoutb =e= sum((l,c,p), Sale(c,p)*Toutb(p)*Doutb(l,c));
Rprod5.. Rprod =e= sum((i,j,l,p), Price(p)*Mpl(i,j)*Loc(i,l)*Conv(p));
Rdisp6.. Rdisp =e= sum((i,j), Mpl(i,j)*(Cdisp(j)+Tdisp(j)));
Sub8.. Sub =e= s*Inv;
Alab9.. Alab =e= Wage*sum(l, Staff(l));
Link(i).. sum(l,Loc(i,l)) =e= 1;
Linkup(l).. Cap(l)$((sum(i, Loc(i,l))>0)) =g= 200;
Linklow(l).. Cap(l)$((sum(i, Loc(i,l))>0)) =l= 25550;
Capacity.. 10*sum(l, Cap(l)) =g= sum((i,j), Mpl(i,j));
MassbalanceS.. sum((i,j), Mpl(i,j)) =e= sum((l,m),Pmon(l,m));
MassbalanceP(p).. sum((l,m), Pmon(l,m)*Conv(p)) =e= sum(c, Sale(c,p));
MassbalanceD(p).. sum((i,j), Mpl(i,j)*Conv(p)) =l= sum((c,l), D(c,p)*Cloc(l,c));
profit.. Z =e= (Ainb + Awh + Amain + Aop + Alab + Aoutb)*Df + Inv - Sub - (Rprod + Rdisp)*Df;
model agriplastic /all/;
solve agriplastic using mip minimizing Z;