$title Many free variables and restart (LP03,SEQ=68) $ontext In this test we check how a solver behaves when there are many free variables and if it restarts from this optimal basis. $offtext $if not set MTYPE $set MTYPE lp $if not set DEMOSIZE $set DEMOSIZE 0 $if not set GLOBALSIZE $set GLOBALSIZE 0 $if not set SKIPITER $set SKIPITER 0 $if not %DEMOSIZE% == 0 $set DEMOSIZE 1 $if not %GLOBALSIZE% == 0 $set GLOBALSIZE 1 $ set KK 20 $if %DEMOSIZE%%GLOBALSIZE% == 11 $set KK 3 Sets i canning plants / seattle, san-diego / j markets / new-york, chicago, topeka / k / 1*%KK% /; Parameters a(i) capacity of plant i in cases / seattle 350 san-diego 600 / b(j) demand at market j in cases / new-york 325 chicago 300 topeka 275 / ; Table d(i,j) distance in thousands of miles new-york chicago topeka seattle 2.5 1.7 1.8 san-diego 3.5 2.8 1.4 ; Scalar f freight in dollars per case per thousand miles /90/ ; Parameter c(i,j) transport cost in thousands of dollars per case ; c(i,j) = f * d(i,j) / 1000 ; Variables xx(k) free variables x(i,j) shipment quantities in cases z total transportation costs in thousands of dollars ; Positive Variable x ; Equations cost define objective function supply(i) observe supply limit at plant i demand(j) satisfy demand at market j stuff silly equation; cost .. z =e= sum((i,j), c(i,j)*x(i,j)); supply(i) .. sum(j, x(i,j)) =l= a(i) ; demand(j) .. sum(i, x(i,j)) =g= b(j) ; stuff.. sum(k, xx(k)) =e= 0; Model lp03 /all/ ; option limcol=0,limrow=0; Solve lp03 using %MTYPE% minimizing z ; abort$( lp03.solvestat <> %solvestat.NormalCompletion% or lp03.modelstat <> %modelstat.Optimal%) 'wrong status codes'; abort$( sum(k, mapval(xx.m(k))=mapval(eps)) <> (card(k)-1)) 'wrong EPS'; Solve lp03 using %MTYPE% minimizing z ; abort$( lp03.solvestat <> %solvestat.NormalCompletion% or lp03.modelstat <> %modelstat.Optimal%) 'wrong status codes'; abort$( sum(k, mapval(xx.m(k))=mapval(eps)) <> (card(k)-1)) 'wrong EPS'; $if %SKIPITER% == 0 abort$( lp03.iterusd > 0) 'too many iters';