$title Example: subsets and multi-dimensional sets

* two basic sets
set months /Jan, Feb, Mar, Apr, May, Jun, Jul, Aug,
	    Sep, Oct, Nov, Dec/;
set weather /wintry, spring-like, summery, fall-like/;

* subset with domain checking
set evenMonths(months) / Feb, Apr, Jun, Aug, Oct, Dec/;

* month-weather associations with domain checking
set
	likely_weather (months, weather) / 
		       (Nov, Dec, Jan, Feb, Mar, Apr).wintry,
		       (Mar, Apr, May, Jun).spring-like,
		       (May, Jun, Jul, Aug, Sep, Oct).summery,
		       (Sep, Oct, Nov).fall-like/;

display likely_weather;