I am very new to Python (I started learning it just yesterday), but I
have encountered a problem.
I want to make a simple script that calculates the n-th root of a given
number (e.g. 4th root of 625--obviously five, but it's just an example
:P), and because there is no nth-root function in Python I will do this
with something like x**(1/n).
However, with some, but not all, decimals, they do not seem to 'equal
themselves'. This is probably a bad way of expressing what I mean, so
I'll give an example:
>>> 0.5
0.5
>>> 0.25
0.25
>>> 0.125
0.125
>>> 0.2
0.20000000000000001
>>> 0.33
0.33000000000000002
As you can see, the last two decimals are very slightly inaccurate.
However, it appears that when n in 1/n is a power of two, the decimal
does not get 'thrown off'. How might I make Python recognise 0.2 as 0.2
and not 0.20000000000000001?
This discrepancy is very minor, but it makes the whole n-th root
calculator inaccurate. :\
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