The use of intervals for the range or domain of a function is very common.
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In computability theory, the domain of a function is taken to be the set of all inputs for which the function is defined.
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Often the parameters are inputs of a function, in which case the technical term for the parameter space is domain of a function.
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Axioms asserting that the domain and range of a function are both sets.
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There are two distinct meanings in current mathematical usage for the notion of the domain of a partial function.
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The domain of a complex-valued function may be extended to include the point at infinity as well.
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The definition of a recursively enumerable set as the domain of a partial function, rather than the range of a total recursive function, is common in contemporary texts.
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The set of all permitted inputs to a given function is called the domain of the function.
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More loosely, a function of a real variable is sometimes taken to mean any function whose domain is a subset of the real line.