[ferret_users] TAX_JDAY returns 366 days each year

[Martin Schmidt <martin.schmidt@xxxxxxxxxxxxxxxxx>]

Hi ferreters,

I need the Julian day of a time axis for tsome calculation and 
discovered the function TAX_JDAY. I tried

define 
axis/t=1-dec-1998:31-jan-2001:1/unit=hours/t0=1-jan-1955/cal=gregorian tax
define grid/t=tax tgrid
let tdummy=0*t[gt=tgrid]
let rjulianday = TAX_JDAY(t[gt=tdummy],tdummy)
list/t=27-feb-1999:02-mar-1999/prec=8 rjulianday

Now look to somewhere else
list/t=31-dec-1999:02-jan-2000/prec=8 rjulianday

Now define it again
let rjulianday = TAX_JDAY(t[gt=tdummy],tdummy)
list/t=27-feb-1999:02-mar-1999/prec=8 rjulianday

28-FEB-1999 21:00 / 2158: 59.000000
28-FEB-1999 22:00 / 2159: 59.000000
28-FEB-1999 23:00 / 2160: 59.000000
01-MAR-1999 00:00 / 2161: 61.000000
01-MAR-1999 01:00 / 2162: 61.000000
01-MAR-1999 02:00 / 2163: 61.000000

Day 60 is missing now. Seems, that touching 2000 marks the year as a 
leap year, which is not taken back returning to 1999.

Best,
Martin Schmidt