Lists as Sets
Mathematica usually keeps the elements of a list in exactly the order you originally entered them. If you want to treat a Mathematica list like a mathematical set, however, you may want to ignore the order of elements in the list.
| Union[list1,list2,...] | give a list of the distinct elements in the  |
| Intersection[list1,list2,...] | give a list of the elements that are common to all the  |
| Complement[universal,list1,...] | give a list of the elements that are in universal, but not in any of the  |
| Subsets[list] | give a list of all subsets of the elements in list |
| DeleteDuplicates[list] | delete all duplicates from list |
Set theoretical functions.
Union gives the elements that occur in
any of the lists.
| Out[1]= |  |
Intersection gives only elements that occur in
all the lists.
| Out[2]= |  |
Complement gives elements that occur in the first list, but not in any of the others.
| Out[3]= |  |
This gives all the subsets of the list.
| Out[4]= |  |
| Out[5]= |  |
