floating_to_decimal(3)  (BSD Compatibility Package)  floating_to_decimal(3)


   NAME
         floating_to_decimal:  single_to_decimal, double_to_decimal,
         extended_to_decimal - convert floating-point value to decimal record

   SYNOPSIS
         cc [ flag... ] file ...  -lucb
         #include <floatingpoint.h>

         void single_to_decimal(px, pm, pd, ps)
         single *px ;
         decimal_mode *pm;
         decimal_record *pd;
         fp_exception_field_type *ps;

         void double_to_decimal(px, pm, pd, ps)
         double *px ;
         decimal_mode *pm;
         decimal_record *pd;
         fp_exception_field_type *ps;

         void extended_to_decimal(px, pm, pd, ps)
         extended *px ;
         decimal_mode *pm;
         decimal_record *pd;
         fp_exception_field_type *ps;

   DESCRIPTION
         The floating_to_decimal functions convert the floating-point value at
         *px into a decimal record at *pd, observing the modes specified in
         *pm and setting exceptions in *ps.  If there are no IEEE exceptions,
         *ps will be zero.

         If *px is zero, infinity, or NaN, then only pd->sign and pd->fpclass
         are set.  Otherwise pd->exponent and pd->ds are also set so that

               (pd->sign)*(pd->ds)*10**(pd->exponent)

         is a correctly rounded approximation to *px.  pd->ds has at least one
         and no more than
          DECIMAL_STRING_LENGTH-1 significant digits because one character is
         used to terminate the string with a NULL.

         pd->ds is correctly rounded according to the IEEE rounding modes in
         pm->rd.  *ps has fp_inexact set if the result was inexact, and has
         fp_overflow set if the string result does not fit in pd->ds because
         of the limitation DECIMAL_STRING_LENGTH.

         If pm->df==floating_form, then pd->ds always contains pm->ndigits
         significant digits.  Thus if *px == 12.34 and pm->ndigits == 8, then
         pd->ds will contain 12340000 and pd->exponent will contain -6.



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   floating_to_decimal(3)  (BSD Compatibility Package)  floating_to_decimal(3)


         If pm->df==fixed_form and pm->ndigits >= 0, then pd->ds always
         contains pm->ndigits after the point and as many digits as necessary
         before the point.  Since the latter is not known in advance, the
         total number of digits required is returned in pd->ndigits; if that
         number >= DECIMAL_STRING_LENGTH, then ds is undefined.  pd->exponent
         always gets -pm->ndigits.  Thus if *px == 12.34 and pm->ndigits == 1,
         then pd->ds gets 123, pd->exponent gets -1, and pd->ndigits gets 3.

         If pm->df==fixed_form and pm->ndigits < 0, then pm->ds always
         contains -pm->ndigits trailing zeros; in other words, rounding occurs
         -pm->ndigits to the left of the decimal point, but the digits rounded
         away are retained as zeros.  The total number of digits required is
         in pd->ndigits.  pd->exponent always gets 0.  Thus if *px == 12.34
         and pm->ndigits == -1, then pd->ds gets 10, pd->exponent gets 0, and
         pd->ndigits gets 2.

         pd->more is not used.

         econvert(3), fconvert, gconvert, printf(3S), and sprintf, all use
         double_to_decimal.

   SEE ALSO
         econvert(3).
         printf(3S) in the Programmer's Reference Manual.





























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