Decimal

Note

To create a Decimal from a float, first convert it to a string.

Links

decimal Decimal fixed point and floating point arithmetic.

Convert

To string:

str(number)

To set the number of decimal places to 2:

>>> 'The price is {:.2f} pounds'.format(Decimal('1'))
'The price is 1.00 pounds'

Import

from decimal import Decimal

Rounding

from decimal import Decimal

bmi = weight / (height * height)
return bmi.quantize(Decimal('.01'))

from decimal import Decimal, ROUND_UP

bmi = weight / (height * height)
return bmi.quantize(Decimal('.01'), rounding=ROUND_UP)

To convert to an int:

>>> from decimal import Decimal, ROUND_UP
>>> value = Decimal('9620.016666666666')
>>> x = value.quantize(Decimal('1.'), rounding=ROUND_UP)
>>> x
Decimal('9621')
>>> int(x)
9261

Tip

round converts the decimal to floating point, so better to use quantize (although I don’t understand the maths behind it).