Description

test

Paul van der Eijk

Small Model of Type : GAMS

Category : GAMS Test library

Main file : loop8.gms

$title 'Test optimization of a control set with a single element' (LOOP8,SEQ=213)

$onText

*test
*
*Paul van der Eijk

$offText

set i /i1*i3/
    j /j1*j3/
    k /k1*k3/
    l /l1*l200/
    m /m1*m2000/;

set jj(j) /j3/;

set A(i,j,k);
A(i,j,k)$(uniform(0,1) <= 0.5)=yes;

parameter B(i,j,k,l,m);
B("i2","j3","k3",l,m)$(uniform(0,1) <= 0.05)=1;

scalar T1 Time without modified control,
       T2 Time with modified control;

T1 = TimeExec;

Loop((A(I,j,k)),
   B(i,j,k,l,m) $= Sum(jj, B(i,jj,k,l,m));
   );

T1 := TimeExec - T1;
T2 := TimeExec;
*note that jj is modified inside the loop to the same element
*because of the assignment, there is no optimization
Loop((A(I,j,k)),
   B(i,j,k,l,m) $= Sum(jj, B(i,jj,k,l,m));
   jj("j3")=yes;
   );
T2 := TimeExec - T2;

display T1,T2;
Abort$(8 * T1 > T2) "Single element control does not improve performance";