chem/KPP/kpp/kpp-2.1/util/UpdateSun.c

   1 void Update_SUN()
   2 {
   3 KPP_REAL SunRise, SunSet;
   4 KPP_REAL Thour, Tlocal, Ttmp;
   5
   6   SunRise = 4.5;
   7   SunSet  = 19.5;
   8   Thour = TIME/3600.0;
   9   Tlocal = Thour - ((int)Thour/24)*24;
  10
  11   if ( (Tlocal >= SunRise) && (Tlocal <= SunSet) ) {
  12     Ttmp = (2.0*Tlocal-SunRise-SunSet)/(SunSet-SunRise);
  13     if (Ttmp > 0) Ttmp =  Ttmp*Ttmp;
  14              else Ttmp = -Ttmp*Ttmp;
  15     SUN = ( 1.0 + cos(PI*Ttmp) )/2.0;
  16   } else {
  17     SUN=0.0;
  18   }
  19 }