How to correctly add floating numbers in Python? - python-2.7

Question

I am trying to add 0.2 value to constant x where x = 8 in a loop that runs to 100. Following is the code
x = 8
>>> for i in range(100):
... x += 0.2
...
>>> x
but everytime I get different answer and calculation always incorrect. I read about Floating Point Arithmetic Issue and Limitations but there should be some way around this. Can I use doubles (if they exists) ? I am using Python 2.7
UPDATE:
import time
x=1386919679
while(1):
x+=0.02
print "xx %0.9f"%x
b= round (x,2)
print "bb %0.9f"%b
time.sleep(1)
output
xx 1386933518.586801529
bb 1386933518.589999914
xx 1386933518.606801510
bb 1386933518.609999895
xx 1386933518.626801491
bb 1386933518.630000114
Desired output
I want correct output, I know If just write print x it will be accurate. But my application require that I should print results with 9 precision. I am newbie so please be kind.

Answer 1

You can use double-precision floating point, sure. You're already using it by default.
As for a way around it:
x += 0.2 * 100
I know that sounds facile, but the solution to floating point imprecision is not setting FLOATING_POINT_IMPRECISION = False. This is a fundamental limitation of the representation, and has no general solution, only specific ones (and patterns which apply to groups of specific situations).
There's also a rational number type which can exactly store 0.2, but it's not worth considering for most real-world use cases.