xorn.hybridnum Namespace Reference

Hybrid fixed-/floating-point numbers. More...

Functions
def	format
	Convert a floating-point number to its hybrid string representation. More...
def	parse
	Convert a hybrid string representation to a floating-point number. More...

Detailed Description

Hybrid fixed-/floating-point numbers.

This module provides formatting and parsing functions for a hybrid number format which uses floating-point numbers as the base of a fixed-point notation. This way, decimal fractions down to an arbitrary (but fixed) number of digits can be represented exactly while still allowing the benefits from a floating-point number format.

As an example, in a format with three fixed digits, both the number 1 (represented as the floating-point value 1000.0) and the number 0.001 (represented as the floating-point value 1.0) can be represented exactly, whereas the number 0.0001 (represented as the floating-point number 0.1) would be subject to conversion errors.

To avoid the usual errors when converting a floating-point number to a string and vice versa, hexadecimal notation is used for the decimals to the floating-point representation.

Function Documentation

def xorn.hybridnum.format	(		x,
			decimal_digits
	)

Convert a floating-point number to its hybrid string representation.

TODO: For efficiency reasons, this should probably be ported to C.

Definition at line 42 of file hybridnum.py.

def xorn.hybridnum.parse	(		s,
			decimal_digits
	)

Convert a hybrid string representation to a floating-point number.

TODO: For efficiency reasons, this should probably be ported to C.

Definition at line 133 of file hybridnum.py.