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<h2>NAME</h2>
<em><b>r.timestamp</b></em> - Print/add/remove a timestamp for a raster map.
<h2>KEYWORDS</h2>
raster
<h2>SYNOPSIS</h2>
<b>r.timestamp</b><br>
<b>r.timestamp help</b><br>
<b>r.timestamp</b> <b>map</b>=<em>name</em> [<b>date</b>=<em>timestamp</em>] [--<b>verbose</b>] [--<b>quiet</b>]
<h3>Parameters:</h3>
<DL>
<DT><b>map</b>=<em>name</em></DT>
<DD>Name of input raster map</DD>
<DT><b>date</b>=<em>timestamp</em></DT>
<DD>Datetime, datetime1/datetime2, or none</DD>
</DL>
<H2>DESCRIPTION</H2>
This command has 2 modes of operation. If no date argument is supplied, then
the current timestamp for the raster map is printed. If a date argument is
specified, then the timestamp for the raster map is set to the specified
date(s). See EXAMPLES below.
<H2>NOTES</H2>
Strings containing spaces should be quoted. For specifying a range
of time, the two timestamps should be separated by a forward slash.
To remove the timestamp from a raster map, use <B>date=</b><em>none</em>.
<H2>EXAMPLES</H2>
<b>r.timestamp map=soils</b><br>
Prints the timestamp for the "soils" raster map. If
there is no timestamp for soils, nothing is printed. If
there is a timestamp, one or two time strings are printed,
depending on if the timestamp for the map consists of a
single date or two dates (ie start and end dates).
<p>
<b> r.timestamp map=soils date='15 sep 1987'</b><br>
Sets the timestamp for "soils" to the single date<br>
"15 sep 1987"
<p>
<b> r.timestamp map=soils date='15 sep 1987/20 feb 1988'</b><br>
Sets the timestamp for "soils" to have the start date<br>
"15 sep 1987" and the end date "20 feb 1988"
<p>
<b> r.timestamp map=soils date=none</b><br>
Removes the timestamp for the "soils" raster map
<H2>TIMESTAMP FORMAT</H2>
The timestamp values must use the format as described in the
GRASS datetime library. The source tree for this library
should have a description of the format. For convience, the
formats as of Feb, 1996 are reproduced here:
<p>
There are two types of datetime values: absolute and
relative. Absolute values specify exact dates and/or times.
Relative values specify a span of time. Some examples will
help clarify:
<p>
<b>Absolute</b><p>
The general format for absolute values is:
<p><tt>
day month year [bc] hour:minute:seconds timezone
<p>
day is 1-31<br>
month is jan,feb,...,dec<br>
year is 4 digit year<br>
[bc] if present, indicates dates is BC<br>
hour is 0-23 (24 hour clock)<br>
mintue is 0-59<br>
second is 0-59.9999 (fractions of second allowed)<br>
timezone is +hhmm or -hhmm (eg, -0600)<br>
<p>
parts can be missing
<p>
1994 [bc]<br>
Jan 1994 [bc]<br>
15 jan 1000 [bc]<br>
15 jan 1994 [bc] 10 [+0000]<br>
15 jan 1994 [bc] 10:00 [+0100]<br>
15 jan 1994 [bc] 10:00:23.34 [-0500]<br>
<p>
</tt>
<b>Relative</b><p>
There are two types of relative datetime values, year-
month and day-second. The formats are:
<p><tt>
[-] # years # months<br>
[-] # days # hours # minutes # seconds
</tt><p>
The words years, months, days, hours, minutes, seconds
are literal words, and the # are the numeric values.<br>
Examples:<p>
<tt>
2 years<br>
5 months<br>
2 years 5 months<br>
100 days<br>
15 hours 25 minutes 35.34 seconds<br>
100 days 25 minutes<br>
1000 hours 35.34 seconds
</tt><p>
The following are <i>illegal</i> because it mixes year-month
and day-second (because the number of days in a month
or in a year vary):<p>
<tt>
3 months 15 days<br>
3 years 10 days
</tt>
<h2>SEE ALSO</h2>
<em><a HREF="v.timestamp.html">v.timestamp</a></em>
<H2>BUGS</H2>
Spaces in the timestamp value are required.
<H2>AUTHOR</H2>
Michael Shapiro, <br>
U.S.Army Construction Engineering Research Laboratory
<p><i>Last changed: $Date: 2003-05-06 18:15:08 +0200 (Tue, 06 May 2003) $</i>
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