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python-3.xnumberspython-3.8rational-number

Why cant I use these rational, numerator & denominator from class numbers.Rational in Python 3.8?

Can someone help me in understanding how to use these rational, numerator & denominator

*class numbers.Rational Subtypes Real and adds numerator and denominator properties, which should be in lowest terms. With these, it provides a default for float().

numerator Abstract.

denominator Abstract.*

Here's the link to the official documentation

Here's the link to official code

enter image description here

Solution

  • The numbers module provides some abstract base classes that you can use if you are implementing your own numeric types. You don't need to use them, but they offer some help in getting things right, if you want it.

    They're not builtin types that you can always access, those are different. The concrete numeric types in Python are int, float, complex and, if you're willing to go into the standard library, fractions.Fraction and decimal.Decimal.

    In the interactive session you show in the question, you're creating a complex object and a float (by dividing integers). These are not the same thing as numbers.Complex or numbers.Rational. And while the numbers.Complex class's API is a close match to how the concrete complex type actually works, the float type is much more different from the abstract numbers.Rational API.

    If you just want to represent a float as a fraction, try calling the as_integer_ratio() method on it. This may not be the fraction you expect! That's because floating point values are not always exact, especially when a binary representation was infinitely repeating and needed to be truncated somewhere.