Note: This is taken from the Chicken Wiki, where a more recent version could be available.

Introduction

The fpio library contains a routines for converting floating-point numbers between IEEE binary representation and decimal string representation. It is based on the gdtoa library by David Gay.

There are two routines included with the library, string->fp and fp->string.

Library procedures

fp->string:: NUMBER [* NDIGITS] -> STRING

Converts the given floating-point number to decimal string representation. If optional argument NDIGITS is positive, the conversion is done to the specified number of decimal places. If NDIGITS is zero (the default) or negative, the conversion is done to the shortest decimal string that rounds to the given floating point value.

string->fp:: STRING [* ROUNDING] -> NUMBER

Converts the given decimal string number to binary IEEE floating point representation. Optional argument ROUNDING is a symbol that can be one of:

toward-zero
indicates rounding-towards-zero mode (the default)
nearest
indicates rounding-towards-nearest mode
toward+Inf
indicates rounding-towards +Inf mode
toward-Inf
indicates rounding-towards -Inf mode

Authors

Ivan Raikov

Version

1.2
Fixes to the file manifest
1.0
Initial version

License

Copyright 2008 Ivan Raikov.

Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided that the above copyright notice appear in all copies and that both that the copyright notice and this permission notice appear in supporting documentation.