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I need some help understanding the difference between two boolean comparisons in the following code: 

x=10.0
for i in range(10):
   x+=0.1
   #print x
print type(x)
print x
print type(11.0)
print x == 11.0  

for i in range(10):
   x-=0.1
   #print x
print type(x)
print x
print type(10.0)
print x == 10.0

The code yields:

<type 'float'>
11.0
<type 'float'>
False
<type 'float'>
10.0
<type 'float'>
True

As you can see all variables are of type float, but when comparing x == 11.0 the boolean comparison returns False. In the next loop, the value of x returns to its original value of 10.0 and when compared returns True.

I'm not sure exactly why one is False and the other is True when I believe both items being compared are of the same value and type in both comparisons. I suspect the issue lies with casting and converting types, but I could be wrong.

mugabits
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