Python has three basic numeric types, unbounded integers, floats (with the precision of C doubles), and complex (for example, 5+0.3j). However, its standard li

Python has three basic numeric types, unbounded integers, floats (with the precision of C doubles), and complex (for example, 5+0.3j). However, its standard library includes both a decimal type and a fraction type. The decimal type has been in the language for over 9 years. The documentation is quite clear [1]. Python's decimal type conforms to IBM's General Decimal Arithmetic Specification [2] which is based on IEEE 754 and IEEE 854. Python's decimal type is very complete. For example Python supports the complete range of rounding options found in these specifications (ROUND_CEILING, ROUND_DOWN, ROUND_FLOOR, ROUND_HALF_DOWN, ROUND_HALF_EVEN, ROUND_HALF_UP, ROUND_UP, and ROUND_05UP). By comparison Dec64 supports only one. Despite having used Python on and off for over 10 years, I've never felt a need to use this decimal type. Integers and floats seem to work for me (although it's nice to have a good decimal implementation available if I need it). [1] http://docs.python.org/3.4/library/decimal.html http://docs.python.org/3.4/library/decimal.html [2] http://speleotrove.com/decimal/decarith.html http://speleotrove.com/decimal/decarith.html