static long ymd_to_scalar (unsigned yr, unsigned mo, unsigned day) {
long scalar;
scalar = day + months_to_days(mo);
if (mo > 2) /* adjust if past February */
scalar -= isleap(yr) ? 1 : 2;
yr--;
scalar += years_to_days(yr);
return scalar;
}
int jdate( unsigned yr, unsigned mo, unsigned day )
{
SEH_PUSH("jdate()");
int which = day + months_to_days( mo );
if ( mo > 2 )
{
which -= isleap( yr ) ? 1 : 2;
}
return which;
}
/*--------------------------------------------------------------------------*/
static long ymd_to_scalar (unsigned year, unsigned month, unsigned day)
{
long scalaire;
scalaire = day + months_to_days(month);
if ( month > 2 )
{
scalaire -= isBissextile(year) ? 1 : 2;
}
year--;
scalaire += years_to_days(year);
return scalaire;
}
void scalar_to_ymd (long scalar, unsigned *yr, unsigned *mo, unsigned *day)
{
static unsigned n; /* compute inverse of years_to_days() */
for ( n = (unsigned)((scalar * 400L) / 146097L); years_to_days(n) < scalar;)
n++; /* 146097 == years_to_days(400) */
*yr = n;
n = (unsigned)(scalar - years_to_days(n-1));
if ( n > 59 ) { /* adjust if past February */
n += 2;
if ( isleap(*yr) )
n -= n > 62 ? 1 : 2;
}
*mo = (n * 100 + 3007) / 3057; /* inverse of months_to_days() */
*day = n - months_to_days(*mo);
}
static void scalar_to_ymd (long scalar,
unsigned *pyr,
unsigned *pmo,
unsigned *pday) {
unsigned n; // compute inverse of years_to_days()
n = (unsigned)((scalar * 400L) / 146097L);
while ((long)years_to_days(n) < scalar) {
n++;
}
for ( n = (unsigned)((scalar * 400L) / 146097L); (long)years_to_days(n) < scalar; )
n++; // 146097 == years_to_days(400)
*pyr = n;
n = (unsigned)(scalar - years_to_days(n-1));
if ( n > 59 ) { // adjust if past February
n += 2;
if ( isleap(*pyr) )
n -= n > 61 ? 1 : 2;
}
*pmo = (n * 100 + 3007) / 3057; // inverse of months_to_days()
*pday = n - months_to_days(*pmo);
return;
}
