On output, produces a string of digits giving the Astronomical Julian Date or
Astronomical Julian Day Number (JDN/JD). In opposite to calendar julian day
\fB%J\fR, it starts the day at noon.
On input, accepts a string of digits (or floating point with the time fraction)
and interprets it as an Astronomical Julian Day Number (JDN/JD).
The Astronomical Julian Date is a count of the number of calendar days
that have elapsed since 1 January, 4713 BCE of the proleptic
Julian calendar, which contains also the time fraktion (after floating point).
The epoch time of 1 January 1970 corresponds to Astronomical JDN 2440587.5.
This value corresponds the julian day used in sqlite-database, and is the same
as result of \fBselect julianday(:seconds, 'unixepoch')\fR.
.IP \fB%EJ\fR
On output, produces a string of digits giving the Calendar Julian Date.
In opposite to julian day \fB%J\fR format group, it produces float number.
In opposite to astronomical julian day \fB%Ej\fR group, it starts at midnight.
On input, accepts a string of digits (or floating point with the time fraction)
and interprets it as a Calendar Julian Day Number.
The Calendar Julian Date is a count of the number of calendar days
that have elapsed since 1 January, 4713 BCE of the proleptic
Julian calendar, which contains also the time fraktion (after floating point).
The epoch time of 1 January 1970 corresponds to Astronomical JDN 2440588.
.IP \fB%Es\fR
This affects similar to \fB%s\fR, but in opposition to \fB%s\fR it parses
or formats local seconds (not the posix seconds).
Because \fB%s\fR has the same precedence as \fB%s\fR (uniquely determines
a point in time), it overrides all other input formats.
.IP \fB%Ex\fR

.IP \fB%I\fR
On output, produces a two-digit number giving the hour of the day
(12-11) on a 12-hour clock.  On input, accepts such a number.
.IP \fB%j\fR
On output, produces a three-digit number giving the day of the year
(001-366).  On input, accepts such a number.
.IP \fB%J\fR
On output, produces a string of digits giving the calendar Julian Day Number.
On input, accepts a string of digits and interprets it as a Julian Day Number.
The Julian Day Number is a count of the number of calendar days
that have elapsed since 1 January, 4713 BCE of the proleptic
Julian calendar.  The epoch time of 1 January 1970 corresponds
to Julian Day Number 2440588.
.IP \fB%k\fR
On output, produces a one- or two-digit number giving the hour of the day

acceptable formats are
.QW "\fImm\fB/\fIdd\fR?\fB/\fIyy\fR?" ,
.QW "\fImonthname dd\fR?\fB, \fIyy\fR?" ,
.QW "\fIday\fB, \fIdd monthname \fR?\fIyy\fR?" ,
.QW "\fIdd monthname yy\fR" ,
.QW "?\fICC\fR?\fIyymmdd\fR" ,
and
.QW "\fIdd\fB\-\fImonthname\fB\-\fR?\fICC\fR?\fIyy\fR" .
The default year is the current year.  If the year is less
than 100, we treat the years 00-68 as 2000-2068 and the years 69-99
as 1969-1999.  Not all platforms can represent the years 38-70, so
an error may result if these years are used.
.TP
\fIISO 8601 point-in-time\fR
.