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).
Julian calendar, which contains also the time fraction (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).
Julian calendar, which contains also the time fraction (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 output, produces a string of digits giving the 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" .
.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
.