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## fpio

Conversion of floating point numbers between binary and decimal representation.

### 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

*[procedure]*

`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.

*[procedure]*

`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

### Version

- 1.4
- Added import of foreign library [thanks to felix]
- 1.3
- Ported to Chicken 4
- 1.2
- Fixes to the file manifest
- 1.0
- Initial version

### License

Copyright 2008-2010 Ivan Raikov.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: - Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. - Neither name of the copyright holders nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND THE CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.