$title examples of conditionals (cond1.gms)
$stitle example of set membership logical condition

set
    days /Sun, Mon, Tue, Wed, Thu, Fri, Sat/
    weekdays(days) /Mon, Tue, Wed, Thu, Fri/;

parameter
  workdone(days)
  lunchtime(days)
;

workdone(days) = 8$weekdays(days) + 4$(not weekdays(days))
  + 2$sameas(days,"Sat");

display workdone;

* $exit

$stitle example of and, or and xor

set i /1*10/;
set j(i), k(i), ix(i), io(i), ia(i);

j(i) = yes$(ord(i) lt 6);
k(i) = yes$(ord(i) ge 4);

ia(i) = yes$(j(i) and k(i));
io(i) = yes$(j(i) or k(i));
ix(i) = yes$(j(i) xor k(i));

display i, j, k, ia, io, ix;

$stitle examples of assignment on the left

set l(i);

j(i)$k(i) = no;
* j(k) = no;
l(io) = yes;
l(ia) = no;

display j,l;

l(i) = yes$io(i);
l(i) = yes$ia(i);

display l;