Function (nonfiction)

A function f takes an input x, and returns a single output f(x). One metaphor describes the function as a "machine" or "black box" that for each input returns a corresponding output.

In mathematics, a function is a relation between a set of inputs and a set of permissible outputs with the property that each input is related to exactly one output.

An example is the function that relates each real number x to its square x2.

The output of a function f corresponding to an input x is denoted by f(x) (read "f of x").

In this example, if the input is −3, then the output is 9, and we may write f(−3) = 9.

Likewise, if the input is 3, then the output is also 9, and we may write f(3) = 9. (The same output may be produced by more than one input, but each input gives only one output.)

In the News

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  Supervillains Forbidden Ratio and Gnotilus form crime team to destroy the Golden ratio.

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  Halting problem is delicious, says supervillain Forbidden Ratio.

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  Asclepius Myrmidon finds Halting problem, forecasts multiple casualties from Pi disaster.

Fiction cross-reference

• Asclepius Myrmidon
• Forbidden Ratio - a mathematical function and supervillain.
• Killer Poke - a software defect for hire, and contract killer for Murder, Incorporated 1.1.
• Pi disaster

Nonfiction cross-reference

• Algorithm (nonfiction)
• Golden ratio (nonfiction)

External links:

• Function (mathematics) @ Wikipedia