Operations in python

Question

Hello, I am making operations and I notice that if I make 1-273.15+273.15 it returns 1, but if I make 0.9-273.15+273.15 it doesn't return 0.9.
Someone knows why that happens?

Answer 1

I solve it using the built-in module decimal:

for decimal import *

Decimal("0.9")-Decimal("273.15")+ Decimal("273.15")

Here is the tip for everyone having this problem as we can see here: https://docs. python.org/3/library/decimal.html

Answer 2

The returned result is essentially 0.9, it's just how fractions are stored and represented. Read more about it under here:
https://en.m.wikipedia.org/wiki/Floating-point_arithmetic#Accuracy_problems