#include #define IGREG (15+31L*(10+12L*1582)) long julday(mm,id,iyyy) int mm,id,iyyy; { long jul; int ja,jy,jm; void nrerror(); if (iyyy == 0) nrerror("JULDAY: there is no year zero."); if (iyyy < 0) ++iyyy; if (mm > 2) { jy=iyyy; jm=mm+1; } else { jy=iyyy-1; jm=mm+13; } jul = (long) (floor(365.25*jy)+floor(30.6001*jm)+id+1720995); if (id+31L*(mm+12L*iyyy) >= IGREG) { ja=0.01*jy; jul += 2-ja+(int) (0.25*ja); } return jul; } #undef IGREG