Numbers¶

int¶

In [1]:
my_int = 6 print(f"value: {my_int}, type: {type(my_int)}") 
value: 6, type: <class 'int'>

float¶

In [2]:
my_float = float(my_int) print(f"value: {my_float}, type: {type(my_float)}") 
value: 6.0, type: <class 'float'>

Note that division of ints produces float:

In [3]:
print(1 / 1) print(6 / 5) 
1.0 1.2

Be aware of the binary floating-point pitfalls (see Decimal for workaround):

In [4]:
val = 0.1 + 0.1 + 0.1 print(val == 0.3) print(val) 
False 0.30000000000000004

Floor division //, modulus %, power **¶

In [5]:
7 // 5
Out[5]:
1
In [6]:
7 % 5
Out[6]:
2
In [7]:
2**3
Out[7]:
8

decimal.Decimal¶

In [8]:
from decimal import Decimal
In [9]:
from_float = Decimal(0.1) from_str = Decimal("0.1") print(f"from float: {from_float}\nfrom string: {from_str}") 
from float: 0.1000000000000000055511151231257827021181583404541015625 from string: 0.1
In [10]:
my_decimal = Decimal("0.1") sum_of_decimals = my_decimal + my_decimal + my_decimal print(sum_of_decimals == Decimal("0.3")) 
True

Operator precedence in calculations¶

Mathematical operator precedence applies. Use brackets if you want to change the execution order:

In [11]:
print(1 + 2**2 * 3 / 6) # 1 + 4 * 3 / 6 == 1 + 12 / 6 == 1 + 2 print((1 + 2**2) * 3 / 6) 
3.0 2.5