arities - meaning and definition. What is arities
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What (who) is arities - definition

FIXED NUMBER OF ARGUMENTS OR OPERANDS THAT A FUNCTION OR OPERATION REQUIRES
Adic; Nullary; Nullary operation; 0-ary function; Nullary function; Adicity; K-ary relation; Arities; N-ary function; Monadic (arity); Niladic; N-ary operation

Arity         
Arity () is the number of arguments or operands taken by a function, operation or relation in logic, mathematics, and computer science. In mathematics, arity may also be named rank, but this word can have many other meanings in mathematics.
arity         
<programming> The number of arguments a function or operator takes. In some languages functions may have variable arity which sometimes means their last or only argument is actually a list of arguments. (1997-07-21)
niladic         
<programming> A less common synonym for "nullary", presumably following the more common monadic, dyadic, etc. The term was in use as early as 1976, and probably originated in APL. [APL: An Interactive Approach, 1976]. (2001-01-27)

Wikipedia

Arity

In logic, mathematics, and computer science, arity ( (listen)) is the number of arguments or operands taken by a function, operation or relation. In mathematics, arity may also be called rank, but this word can have many other meanings. In logic and philosophy, arity may also be called adicity and degree. In linguistics, it is usually named valency.