Self-map
= Self-map
{title2=$f:X\to X$}
= Endofunction
{synonym}
A <self-map> is a <function> whose <domain of a function> and <codomain> are the same <set>. It need not be a <bijection>: a <constant function> on a two-element <set> is a <self-map> that merges its <inputs>. <Self-maps> can always be composed with one another, and all <self-maps> of a specified <set> form its <full transformation monoid>.