Python - Numeric Decimal Type
Introduction
The decimal object, formally known as Decimal.
With decimals, we can have a floating-point value that always retains just two decimal digits.
We can specify how to round or truncate the extra decimal digits beyond the object's cut off.
The decimal type is useful for representing fixed-precision quantities like sums of money.
Demo
from decimal import Decimal print( 0.1 + 0.1 + 0.1 - 0.3 ) # Python 3.3 print( Decimal('0.1') + Decimal('0.1') + Decimal('0.1') - Decimal('0.3') )
Result
Here, we create decimal objects by calling the Decimal constructor function in the decimal module.
When decimals of different precision are mixed in expressions, Python converts up to the largest number of decimal digits automatically:
Demo
from decimal import Decimal print( Decimal('0.1') + Decimal('0.10') + Decimal('0.10') - Decimal('0.30') )
Result
You can create a decimal object from a floating-point object via a call of decimal.Decimal.from_float(1.25).
Demo
from decimal import Decimal print( Decimal(0.1) + Decimal(0.1) + Decimal(0.1) - Decimal(0.3) )
Result
