NumeratorDenominator

NumeratorDenominator[expr]

gives the list {Numerator[expr],Denominator[expr]} of expr.

Details and Options

  • Numerator picks out terms that do not have superficially negative exponents. Denominator picks out the remaining terms.
  • An exponent is "superficially negative" if it has a negative number as a factor.
  • The standard representation of rational expressions as products of powers means that you cannot simply use Part to extract numerators.
  • NumeratorDenominator can be used on rational numbers.
  • NumeratorDenominator automatically threads over lists.

Examples

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Basic Examples  (2)

Extract the numerator and denominator of a rational number:

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Extract the numerator and denominator of a rational expression:

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Scope  (5)

Options  (2)

Properties & Relations  (1)

Neat Examples  (1)

Introduced in 2019
(12.0)