How to manage rounding and decimals?

Question

a = 1.4999999999999999
b = round(a)
print(b)
2
c = 1.499999999999999
d = round(c)
print(d)
1
-So my question is what is the simplest way to cut down the number of decimal places taken into account and what would be the result? 1 or 2?
-Second question: What function of c would make the result of print(d) 2 instead of 1?
-Third question: Is there a simple way to always express the bigger number (so that even if it's only 1.14, you get "2")?
-Fourth question: Is there a simple way (and what it is) to make up your own rounding system? ...for example let's say that everything above 1.33 is "2" and bellow 1.33 is "1".

Answer 1

1)
As described in the documentation linked in your previous question, Python takes into account 17 digits after floating point. That's why a and c are different from each other.
https://docs.python.org/3/tutorial/floatingpoint.html

2)
We need to understand the rounding algorithm that modern Python uses
https://docs.python.org/3/library/functions.html#round

3)
"The bigger number"/ "rounding up" is math.ceil
("The smaller number"/ " rounding down" would be math.floor)

4)
You could write an function for it.
E.g:
if (math.ceil(x) - x > 1/3):
return math.ceil(x)
else:
return math.floor(x)