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Welcome to the Mixed Number Fractions wiki.

Easily input, display, and convert mixed number fractions in Python.

Currently supported Python versions: 3.x

About
The Mixed Number Fraction (Mixed) class is based on the standard library Fraction class. It was designed to be able to do anything and everything that a standard Fraction does, and a bit more. The Mixed constructor creates a Rational, as it inherits from Fraction which, in turn, inherits from numbers.Rational.

Usage

class mixed_fractions.Mixed(whole_number=0, numerator=0, denominator=1)
class mixed_fractions.Mixed(numerator=0, denominator=1)
class mixed_fractions.Mixed(other_mixed)
class mixed_fractions.Mixed(other_fraction))
class mixed_fractions.Mixed(float)
class mixed_fractions.Mixed(decimal)
class mixed_fractions.Mixed(string)

The first version requires that whole_number, numerator, and denominator are instances of numbers.Rational and returns a new Mixed instance with value whole_number + numerator/denominator. If denominator is 0, it raises a ZeroDivisionError. The second version requires that numerator and denominator are instances of numbers.Rational and returns a new Mixed instance with value numerator/denominator, exactly as standard Fraction does, and will also raise a ZeroDivisionError if denominator is 0. The third and fourth versions requires that other_mixed( or other_fraction) is an instance of numbers.Rational and returns a Mixed instance with the same value. The next two versions accept either a float or a decimal.Decimal instance, and return a Mixed instance with exactly the same value. Note that due to the usual issues with binary floating-point, the argument to Mixed(1.1) is not exactly equal to 1 1/10 (11/10), and so Mixed(1.1) does not return Mixed(1,1,10) as one might expect. The last version of the constructor expects a string or unicode instance. Unsupported types being passed to a Mixed constructor will raise a TypeError. The form for the string instance may be any of the following:

[sign] whole_number numerator '/' denominator

or

[sign] numerator '/' denominator

or

[sign] whole_number

where the optional sign may be either ‘+’ or ‘-‘ and whole_number, numerator, and denominator (if present) are strings of decimal digits. In addition, any string that represents a finite value and is accepted by the float constructor is also accepted by the Mixed constructor. The string representation of denominator, if 0, will raise a ZeroDivisionError. An otherwise invalid string will raise a ValueError. In any form, the input string may also have leading and/or trailing whitespace. Here are some examples:

>>> from mixed_fractions import Mixed
>>> Mixed(16,-10)
Mixed(-1, 3, 5)
>>> Mixed(6,7,8)
Mixed(6, 7, 8)
>>> Mixed(123)
Mixed(123, 0, 1)
>>> Mixed()
Mixed(0, 0, 1)
>>> Mixed('3/7')
Mixed(0, 3, 7)
>>> Mixed('-3/7')
Mixed(0, -3, 7)
>>> Mixed('1.414213 \t\n')
Mixed(1, 414213, 1000000)
>>> Mixed('-.125')
Mixed(0, -1, 8)
>>> Mixed('7e-6')
Mixed(0, 7, 1000000)
>>> Mixed(2.25)
Mixed(2, 1, 4)
>>> Mixed(1.1)
Mixed(1, 225179981368525, 2251799813685248)
>>> from decimal import Decimal
>>> Mixed(Decimal('1.1'))
Mixed(1, 1, 10)

The Mixed class inherits from the fractions.Fraction class which inherits from the abstract base class numbers.Rational. Mixed implements all of the methods and operations from those classes. Mixed instances are hashable, and should be treated as immutable. In addition, Mixed has the following properties and methods:

fnumerator
Fractional portion numerator in lowest term. e.g. Mixed(3,4,5).fnumerator will yield 4.

whole
Mixed % 1 e.g. Mixed(3,4,5).whole will yield 3.

to_fraction()
Converts Mixed to Fraction. e.g. Mixed(3,4,5).to_fraction() will yield Fraction(19,5)