Complement of set

GAMS
1

Hello
Is it possible to define complement of a set in gams?
Thanks

2

Hi
Yes this is possible as follows

set all  'Overall set'  /i1*i10/,
     s1(all) 'Subset of overall set' /i1,i2, i9,i10/,
     s2(all) 'Complement set';
     
 s2(all)$(not s1(all)) = YES;
 
 display s2;

gives the following

----      7 SET s2  Complement set

i3,    i4,    i5,    i6,    i7,    i8

I hope this helps
Renger