Can you explain?

Question

I was messing around with floats, then I saw that 0.1+0.2 made something other than 0.3. Why?

Answer 1

Floating point arithmetic has built-in problems as it's based on a binary approximation of numbers.

Explained here:
https://docs.python.org/3/tutorial/floatingpoint.html

If you want to get just 0.3, just use round() function:

round( 0.1+0.2, 1 )
round( num, round_place)

Answer 2

What happens can be compared to the problems you face when you want to express 1/3 or 1/7 as decimal number like 0.333... or 0.142... with a limited number of digits:
You have to truncate somewhere.

The best you can do is minimize the deviation by proper rounding. But there is no exact representation

Answer 3

Ok