Real numbers with a multi-valued logical classification
This article is about the mathematical generalization of a real number as a connected set of possible values. For for a game value which is incomparable with zero, seeFuzzy game.
Fuzzy arithmetic
Afuzzy number is a generalization of a regularreal number in the sense that it does not refer to one single value but rather to a connected set of possible values, where each possible value has its own weight between 0 and 1.[1] This weight is called themembership function. A fuzzy number is thus a special case of a convex, normalizedfuzzy set of thereal line.[2] Just likefuzzy logic is an extension ofBoolean logic (which uses absolute truth and falsehood only, and nothing in between), fuzzy numbers are an extension of real numbers. Calculations with fuzzy numbers allow the incorporation ofuncertainty on parameters, properties, geometry, initial conditions, etc. The arithmetic calculations on fuzzy numbers are implemented using fuzzy arithmetic operations, which can be done by two different approaches: (1)interval arithmetic approach;[3] and (2) the extension principle approach.[4]
A fuzzy number is equal to a fuzzy interval.[5] The degree of fuzziness is determined by the a-cut which is also called the fuzzy spread.[citation needed]