| The set S is called the domain of the function, and the set T is called the codomain of the function. |
| The user accomplished this pairing by highlighting r in the domain and e in the codomain, and clicking the map button. |
| In a computer program, the data types of the arguments to a function and the data type of the return value specify respectively, the domain and codomain of a function. |
| For example, if a unary function is considered as a set of ordered pairs, then the domain and codomain are given by the first and second projections, respectively. |
| Functions that have the same domain and codomain may be quite different, however, by abstraction, they are of the same sort or type. |
| For similar reasons, 2D sheets only display nicely if their codomain is 8 bits deep. |
