# Identity function

An **identity function**, (also called an identity relation or identity map ) is a function that always returns the same value that was used as its argument. In equations, the function is given by `f(x) = x`

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An **identity function**, (also called an identity relation or identity map ) is a function that always returns the same value that was used as its argument. In equations, the function is given by `f(x) = x`

.