In
mathematics, a
fixed point (sometimes shortened to
fixpoint, also known as an
invariant point) of a
function is an element of the function's
domain that is mapped to itself by the function. That is to say,
c is a fixed point of the function
f(
x)
if and only if f(
c) =
c. This means
f(
f(...
f(
c)...)) =
fn(
c) =
c, an important terminating consideration when recursively computing
f. A set of fixed points is sometimes called a
fixed set.