My professor wrote the second code snippet during a demo. Their output was a float. For me, only the first code snippet is a float. Any idea why there is a difference? The second code snippet seems to have integers divided by integers, added to integers so I'm not sure why it was converted to a float.
n = 4
total = 0
for i in range(n+1):
total = total + 1 / float(2**i)
return total
n = 4
total = 0
for i in range(n+1):
total = total + 1 / 2**i
return total
As khelwood has mentioned, In Python 2 when you divide an integer with an integer, the result is also an integer, But in Python 3, the result becomes a float. Let me demonstrate
# 10/6 == 1
# 10/3 == 3
Much like C++'s division operator, it drops any fractional value and returns an integer. However this changes for Python 3
#10/6 == 1.6666666666666667
#10/3 == 3.3333333333333335
In python 3, the division operator will return float(dividing int/int)
If you want float division in Python 2, you need to
from __future__ import division like Jan mentioned.
This will let you divide to get a float value
3 // 2 is 1 int in Python 3 but was also in 2, explicit integer division. the old way for float div there was 3 / 2.0 which is 1.5 also in Python 2 of course. but the future import is nice for 3 compatibility.In Python 2, division of two ints produces an int. In Python 3, it produces a float. I think you are using python 2, and you Professor python 3.
from __future__ import division should be mentioned
floatis the difference :-) what python version do you use?int/int=int. In Python 3,int/int=floatfrom __future__ import division:-)