src/rational/division/cl_RA_round12.cc

   1 // round1().
   2
   3 // General includes.
   4 #include "cl_sysdep.h"
   5
   6 // Specification.
   7 #include "cl_rational.h"
   8
   9
  10 // Implementation.
  11
  12 #include "cl_RA.h"
  13 #include "cl_integer.h"
  14
  15 const cl_I round1 (const cl_RA& x, const cl_RA& y)
  16 {
  17 // Methode:
  18 // x = a/b, y = c/d -> liefere (round (* a d) (* b c)).
  19 // x Integer -> dito mit b=1.
  20 // y Integer -> dito mit d=1.
  21 // x und y Integer -> bekannt.
  22         if (integerp(x)) {
  23                 DeclareType(cl_I,x);
  24                 if (integerp(y)) {
  25                         DeclareType(cl_I,y);
  26                         return round1(x,y);
  27                 } else {
  28                         DeclareType(cl_RT,y);
  29                         var const cl_I& c = numerator(y);
  30                         var const cl_I& d = denominator(y);
  31                         return round1(x*d,c);
  32                 }
  33         } else {
  34                 DeclareType(cl_RT,x);
  35                 var const cl_I& a = numerator(x);
  36                 var const cl_I& b = denominator(x);
  37                 if (integerp(y)) {
  38                         DeclareType(cl_I,y);
  39                         return round1(a,b*y);
  40                 } else {
  41                         DeclareType(cl_RT,y);
  42                         var const cl_I& c = numerator(y);
  43                         var const cl_I& d = denominator(y);
  44                         return round1(a*d,b*c);
  45                 }
  46         }
  47 }