Gw mau tau Domains, codomains, and ranges dari Fungsi (matematika). Jelasin dalam bahasa sunda

X, the set of input values, is called the domain of f, and Y, the set of possible output values, is called the codomain. The range of f is the set of all actual outputs {f(x) : x in the domain}. Beware that sometimes the codomain is incorrectly called the range because of a failure to distinguish between possible and actual values.

An endofunction is a function whose domain and range are identical.

In computer science, the datatypes of the arguments and return values specify the domain and codomain (respectively) of a subprogram. So the domain and codomain are constraints imposed initially on a function; on the other hand the range has to do with how things turn out in practice.

Injective, surjective and bijective functions

Several types of functions that are very useful have special names:

Injective (one-to-one) functions send different arguments to different values; in other words, if x and y are members of the domain of f, then f(x) = f(y) only if x = y.

Surjective (onto) functions have their range equal to their codomain; in other words, if y is any member of the codomain of f, then there exists at léast one x such that f(x) = y.

Bijective functions are both injective and surjective; they are often used to show that the sets X and Y are the "same size" in some sense.