Python Convert fraction to decimal
I want to convert 1/2 in python so that when i say print x (where x = 1/2) it returns 0.5
I am looking for the most basic way of doing this, without using any split functions, loops or maps
I have tried float(1/2) but I get 0... can someone explain me why and how to fix it?
Is it possible to do this without modifying the variable x= 1/2 ??
in python 3.x any division returns a float;
>>> 1/2 0.5
to achieve that in python 2.x, you have to force float conversion:
>>> 1.0/2 0.5
or to import the division from the "future"
>>> from __future__ import division >>> 1/2 0.5
An extra: there is no a built-in fraction type, but there is in the official library:
>>> from fractions import Fraction >>> a = Fraction(1, 2) #or Fraction('1/2') >>> a Fraction(1, 2) >>> print a 1/2 >>> float(a) 0.5
and so on...
You're probably using Python 2. You can "fix" division by using:
from __future__ import division
at the start of your script (before any other imports). By default in Python 2, the / operator performs integer division when using integer operands, which discards fractional parts of the result.
This has been changed in Python 3 so that / is always floating point division. The new // operator performs integer division.
Alternatively, you can force floating point division by specifying a decimal or by multiplying by 1.0. For instance (from inside the python interpreter):
>>> print 1/2 0 >>> print 1./2 0.5 >>> x = 1/2 >>> print x 0 >>> x = 1./2 >>> print x 0.5 >>> x = 1.0 * 1/2 >>> print x 0.5
EDIT: Looks like I was beaten to the punch in the time it took to type up my response :)
If the input is a string,then you could use Fraction directly on the input:
from fractions import Fraction x='1/2' x=Fraction(x) #change the type of x from string to Fraction x=float(x) #change the type of x from Fraction to float print x
There is no quantity 1/2 anywhere. Python does not represent rational numbers with a built-in type - just integers and floating-point numbers. 1 is divided by 2 - following the integer division rules - resulting in 0. float(0) is 0.