// cl_LF_shortenwith(). // General includes. #include "cl_sysdep.h" // Specification. #include "cl_LF.h" // Implementation. #include "cln/abort.h" #undef MAYBE_INLINE2 #define MAYBE_INLINE2 inline #include "cl_LF_precision.cc" #undef MAYBE_INLINE #define MAYBE_INLINE inline #include "cl_LF_exponent.cc" namespace cln { const cl_LF cl_LF_shortenwith (const cl_LF& x, const cl_LF& y) { // Methode: // x = 0.0 -> Precision egal, return x. // ex := float_exponent(x), dx := float_digits(x), 1 ulp(x) = 2^(ex-dx). // ey := float_exponent(y). // Falls ex-dx < ey, x von Precision dx auf ex-ey verkürzen. var sintL ey = float_exponent(y); var sintL ex = float_exponent(x); var uintC dx = float_precision(x); if (dx==0) // zerop(x) ? return x; var sintL ulpx = ex - dx; if ((ex<0 && ulpx>=0) // underflow? || (ulpx < ey) ) { // Now ex-dx < ey, hence ex-ey < dx. var uintL new_dx; if (ex < ey) new_dx = intDsize*LF_minlen; else if ((new_dx = ex - ey) < intDsize*LF_minlen) new_dx = intDsize*LF_minlen; var uintL len = ceiling(new_dx,intDsize); if (intDsize*len < dx) return shorten(x,len); else return x; } else return x; } } // namespace cln