(mathematics) Any function whose value may be computed using a Turing machine.

(probability theory) Any function whose integral over a set gives the probability that a random variable has a value in that set

(medicine) Any of several diagnostic procedures that test the blood clotting function of platelets

plural of higher-order function

(computer science) A function that takes one or more functions as an input, and returns a function as a result.

(number theory, analytic number theory, uncountable) The function ζ defined by the Dirichlet series 𝜁(s)=∑ₙ₌₁ ᪲1/(nˢ)=1/(1ˢ)+1/(2ˢ)+1/(3ˢ)+1/(4ˢ)+⋯, which is summable for points s in the complex half-plane with real part > 1; the analytic continuation of said function, being a holomorphic function defined on the complex numbers with pole at 1.

Alternative spelling of Riemann zeta function

plural of adaptive-control function

(medicine) A test of the function of lungs, such as spirometry.

plural of inverse trigonometric function