objection

n 1: an expression of opposition to a course of action [syn: {expostulation},

{remonstrance}]

2: the speech act of objecting

3: the act of protesting; a public (often organized)

manifestation of dissent [syn: {protest}, {dissent}]

bijection

A {function} is bijective or a bijection or a

one-to-one correspondence if it is both {injective} (no two

values map to the same value) and {surjective} (for every

element of the {codomain} there is some element of the

{domain} which maps to it). I.e. there is exactly one element

of the domain which maps to each element of the codomain.

Only bijective functions have inverses f' where f(f'(x)) ◦

f'(f(x)) ◦ x.

See also {injection}, {surjection}, {isomorphism}.

(1999-08-29)