(mathematics) Any function whose values are points

(mathematical analysis) A function whose codomain is a topological space and domain is a measurable space, with the property that the inverse image of every open set in its codomain is a measurable set in its domain.

(mathematics) A function whose domain is a subset of the set on which it is formally defined; i.e., a function f: X→Y for which values f(x) are defined only for x ∈ W, where W ⊆ X.

(mathematics) Any function whose value repeats after the regular addition of a period to its independent variable; i.e., a function ƒ such that, for some positive constant p, ƒ(x + p) = ƒ(x) for all x.

(mathematics) A function where the independent variable is raised to a particular real number power.

(astronomy) A function that describes the angular distribution of light reflected from a body when illuminated from a specific direction

(mathematics) A generalization of the indicator function for a fuzzy set which assigns a truth value (0 or 1) to each element.

(computing) Any function that uses recursion and can call itself until a certain condition is met

(mathematics, complex analysis, algebraic geometry) Any function expressible as the quotient of two (coprime) polynomials (and which thus has poles at a finite, discrete set of points which are the roots of the denominator).

(mathematics) A function of one or more independent variables, at least one of which is itself a function of one or more other independent variables; a function of function(s).