code / tomo

   1 #ifndef FPCONV_H
   2 #define FPCONV_H
   3 
   4 // This file defines a function to convert floating point numbers to strings.
   5 // For license, see: fpconv_license.txt
   6 
   7 /* Fast and accurate double to string conversion based on Florian Loitsch's
   8  * Grisu-algorithm[1].
   9  *
  10  * Input:
  11  * fp -> the double to convert, dest -> destination buffer.
  12  * The generated string will never be longer than 24 characters.
  13  * Make sure to pass a pointer to at least 24 bytes of memory.
  14  * The emitted string will not be null terminated.
  15  *
  16  * Output:
  17  * The number of written characters.
  18  *
  19  * Exemplary usage:
  20  *
  21  * void print(double d)
  22  * {
  23  *      char buf[24 + 1] // plus null terminator
  24  *      int str_len = fpconv_dtoa(d, buf);
  25  *
  26  *      buf[str_len] = '\0';
  27  *      puts(buf);
  28  * }
  29  *
  30  */
  31 
  32 int fpconv_dtoa(double fp, char dest[24]);
  33 
  34 #endif
  35 
  36 /* [1] http://florian.loitsch.com/publications/dtoa-pldi2010.pdf */