Fast arbitrary precision correctly-rounded decimal floating point arithmetic.
The cdecimal package is a fast drop-in replacement for the decimal module in Python’s standard library. Both modules provide complete implementations of Mike Cowlishaw/IBM’s General Decimal Arithmetic Specification.
Both cdecimal and the underlying library - libmpdec - are extremely well tested. libmpdec is one of the few open source projects with 100% code coverage. cdecimal is rigorously tested against decimal.py.
Typical performance gains are between 30x for I/O heavy benchmarks and 80x for numerical programs. In a database benchmark, cdecimal exhibits a speedup of 12x over decimal.py.
Since cdecimal is compatible with decimal.py, the official documentation is valid. For the few remaining differences, refer to the second link.
The build process requires a working C compiler and a full Python install with development headers. Linux distributions often ship the Python header files as a separate package, called python-dev or python-devel.
Install headers on Debian/Ubuntu: