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Mathematica Teacher's Edition

Built-in Functions

Programming

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NumericQ

NumericQ[expr] gives True if expr is a numeric quantity, and False otherwise.

An expression is considered a numeric quantity if it is either an explicit number or a mathematical constant such as Pi.
In most cases, NumericQ[expr] gives True whenever N[expr] would yield an explicit number.
See The Mathematica Book on the web: Section 2.3.5 and Section 3.1.2.
See also: NumberQ.

Further Examples