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Gcal 3.01

G.2.1.9 Moon phase %[format]?[date] special texts

Gcal uses a very simple algorithm for detecting the Moon phase, which computes approximate values only. The Moon phase is always calculated for 0 o'clock Universal time (UTC/GMT). See section Calendar option `--time-offset=argument', how to change the base time for which the astronomical functions are calculated. The following Moon phase %[format]?[date] special texts are respected:

%O[date]

Is replaced by the Moon phase text of the current day of year, e.g.:

The text `Moon phase %O , %n' will be expanded to
==> `Moon phase 94%+, 22-Dec-1996', in case the actual system date is the 22nd December 1996.

The constructed Moon phase text consists of a percent value, which informs about the illuminated fraction of the Moon's disk, and a trailing sign that tells something about the state of the Moon. A trailing `+' sign indicates a waxing Moon, a `-' sign a waning Moon, a `@' sign indicates the Full Moon phase, and a `!' sign the New Moon phase.

%>03*O[date]

Is replaced by the 3-digit Moon phase text with leading zeroes of the current day of year, e.g.:

The text `Moon phase %>03*O0@t+1 , %n+1' will be expanded to
==> `Moon phase 098%+, 23-Dec-1996', in case the actual system date is the 22nd December 1996.

The constructed Moon phase text consists of a percent value, which informs about the illuminated fraction of the Moon's disk, and a trailing sign that tells something about the state of the Moon. A trailing `+' sign indicates a waxing Moon, a `-' sign a waning Moon, a `@' sign indicates the Full Moon phase, and a `!' sign the New Moon phase.

%Z[date]

Is replaced by the Moon phase text graphics of the current day of year, e.g.:

The text `Date %n %Z -- Moon phase %>03*O ~Text' will be expanded to
==> `Date 08-Mar-1995 '
==> ` ( @@@@@@'
==> ` ( @@@@@@@@@'
==> ` ( @@@@@@@@@@@'
==> ` ( @@@@@@@@@@@@'
==> ` ( @@@@@@@@@@@@@'
==> `( @@@@@@@@@@@@@'
==> `( @@@@@@@@@@@@@'
==> ` ( @@@@@@@@@@@@@'
==> ` ( @@@@@@@@@@@@'
==> ` ( @@@@@@@@@@@'
==> ` ( @@@@@@@@@'
==> ` ( @@@@@@@ -- Moon phase 041%+'
==> `Text', in case the actual system date is the 8th March 1995.

See section Fixed date option `--moonimage-lines=number', how to change the size of a Moon phase text graphics.

A possibly specified format within this special text is ignored by Gcal.