Indicator Function

In mathematics, an indicator function or a characteristic function is a function defined on a set that indicates membership of an element in a subset of, having the value 1 for all elements of A and the value 0 for all elements of X not in A.

Read more about Indicator Function:  Definition, Remark On Notation and Terminology, Basic Properties, Mean, Variance and Covariance, Characteristic Function in Recursion Theory, Gödel's and Kleene's representing Function, Characteristic Function in Fuzzy Set Theory

Famous quotes containing the word function:

    Uses are always much broader than functions, and usually far less contentious. The word function carries overtones of purpose and propriety, of concern with why something was developed rather than with how it has actually been found useful. The function of automobiles is to transport people and objects, but they are used for a variety of other purposes—as homes, offices, bedrooms, henhouses, jetties, breakwaters, even offensive weapons.
    Frank Smith (b. 1928)