(mathematics) a mathematical relation such that each element of a given set (the domain of the function) is associated with an element of another set (the range of the function)
what something is used for
the actions and activities assigned to or required or expected of a person or group
a relation such that one thing is dependent on another
a formal or official social gathering or ceremony
a vaguely specified social event
a set sequence of steps, part of larger computer program
动词 function:
perform as expected when applied
serve a purpose, role, or function
perform duties attached to a particular office or place or function
