The number of arguments to a function is called it's arity, and is used to help identify the functions.

函数的参数数量称为元数(arity)，用于帮助标识函数。

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In a finite universe of discourse, one can represent the assignments of predicates with arity n by n-dimensional arrays.

在有穷论域下，可以用n维数组来表示对n元谓词的赋值。

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For instance, properties are assigned by one-dimensional arrays, predicates of arity 2 by two-dimensional arrays, and so on.

例如，性质用一维数组赋值，2元谓词用2维数组赋值，等等。

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