Description

This test makes sure that we do not get a 'Data not sorted' error when the
scenario set contains a 'not sorted' uel.

Contributor: Lutz Westermann

Small Model of Type : GAMS

Category : GAMS Test library

Main file : scensol2.gms

$title Test handling of unsorted scenario UELs in GUSS (SCENSOL2,SEQ=533)

$onText
This test makes sure that we do not get a 'Data not sorted' error when the
scenario set contains a 'not sorted' uel.

Contributor: Lutz Westermann
$offText


Sets
     s   scenarios        / seattle,  los-angeles, san-diego /
     i   canning plants   / seattle,  san-diego              /
     j   markets          / new-york, chicago,     topeka    / ;

Parameters

     a(i)  capacity of plant i in cases
       /    seattle     350
            san-diego   600  /

     b(j)  demand at market j in cases
       /    new-york    325
            chicago     300
            topeka      275  / ;

Table d(i,j)  distance in thousands of miles
                  new-york       chicago      topeka
    seattle          2.5           1.7          1.8
    san-diego        2.5                        1.4  ;

Scalar f  freight in dollars per case per thousand miles  /90/ ;

Parameter c(i,j)  transport cost in thousands of dollars per case ;

         c(i,j) = f * d(i,j) / 1000 ;

Variables
     x(i,j)  shipment quantities in cases
     z       total transportation costs in thousands of dollars ;

Positive Variable x ;

Equations
     cost        define objective function
     supply(i)   observe supply limit at plant i
     demand(j)   satisfy demand at market j ;

cost ..        z  =e=  sum((i,j),  f * d(i,j) / 1000 *x(i,j)) ;

supply(i) ..   sum(j, x(i,j))  =l=  a(i) ;

demand(j) ..   sum(i, x(i,j))  =g=  b(j) ;

Equation e dummy n row;  e.. sum((i,j), x(i,j)) =n= 3;

Model transport /all/ ;

set dict   / s.scenario   . ''
             d.   param   .ds
             x.   level   .xx /

Parameter
    ds(s,i,j)  updater for d
    xx(s,i,j)  collector for level of x;

ds(s,i,j)  = max(0,uniform(-5,2)) + eps;

Solve transport using lp minimizing z scenario dict;

* If we get a license error (global solver) just terminate
if (transport.modelstat=%modelStat.licensingProblem%,
    abort.noerror 'too big for global solvers');

display xx;

set Error(s) No solution found;
Error(s) = sum((i,j),xx(s,i,j)) = 0;
abort$(card(error)) 'Missing solution for some scenarios', error;