Geo::METAR - Process aviation weather reports in the METAR format.
use Geo::METAR; use strict;
my $m = new Geo::METAR;
$m->metar("KFDY 251450Z 21012G21KT 8SM OVC065 04/M01 A3010 RMK 57014");
print $m->dump;
exit;
METAR reports are available on-line, thanks to the National Weather Service. Since reading the METAR format isn't easy for non-pilots, these reports are relatively useles to the common man who just wants a quick glace at the weather.
Here is how you might use the Geo::METAR module.
One use that I have had for this module is to query the NWS METAR page (using the LWP modules) at http://weather.noaa.gov/cgi-bin/mgetmetar.pl?cccc=KFDY to get an up-to-date METAR. Then, I scan thru the output, looking for what looks like a METAR string (that's not hard in Perl). Oh, KFDY can be any site location code where there is a reporting station.
I then pass the METAR into this module and get the info I want. I can then update my home page with the current temperature, sky conditions, or whatnot.
The following functions are defined in the AcctInfo module. Most of them are public, meaning that you're supposed to use them. Some are private, meaning that you're not supposed to use them -- but I won't stop you. Assume that functions are public unless otherwise documented.
metar()metar() is the function to whwich you should pass a METAR string. It
will take care of decomposing it into its component parts converting
the units and so on.
Example: $m->metar("KFDY 251450Z 21012G21KT 8SM OVC065 04/M01 A3010 RMK 57014");
debug()debug() toggles debugging messages. By default, debugging is turned
off. Turn it on if you are developing METAR or having trouble with
it.
debug() understands all of the folloing:
Enable Disable
------ -------
1 0
'yes' 'no'
'on' 'off'
If you contact me for help, I'll likely ask you for some debugging output.
Example: $m->debug(1);
dump()dump() will dump the internal data structure for the METAR in a
semi-human readable format.
Example: $m->dump;
version()version() will print out the current version.
Example: print $m->version;
_tokenize()Called internally to break the METAR into its component tokens.
_process()Used to make sense of the tokens found in _tokenize().
After you've called metar(), you'd probably like to get at the individual values for things like temperature, dew point, and so on. You do that by accessing individual variables via the METAR object.
This section lists those variables and what they represent.
If you call dump(), you'll find that it spits all of these out in roughly this order, too.
Test suite is small and incomplete. Needs work yet.
Older versions of this module were installed as ``METAR'' instaed of ``Geo::METAR''
find() method.I should add a function called find() which can be passed a big chunk
of text (or a ref to one) and a site identifier. It will scan through
the text and find the METAR. The result can be fed back into this
module for processing.
That'd be cool, I think.
There currently aren't any known BUGS (features which don't work as advetised). There are lacking features. See the TODO section for more on that.
There is a TODO file included in the Geo::METAR distribution listing the outstanding tasks that I or others have devised. Please check that list before you submit a bug report or request a new feture. It might already be on the TODO list.
Copyright 1997-2000, Jeremy D. Zawodny <Jeremy@Zawodny.com>
Geo::METAR is covered under the GNU Public License (GPL) version 2 or later.
The Geo::METAR Web site is located at:
http://www.wcnet.org/~jzawodn/perl/Geo-METAR/
In addition to my work on Geo::METAR, I've received ideas, help, and patches from the following folks:
* Otterboy <jong@watchguard.com>
Random script fixes and initial debugging help
* Remi Lefebvre <remi@solaria.dhis.org>
Debian packaging as libgeo-metar-perl.deb.
* Mike Engelhart <mengelhart@earthtrip.com>
Wind direction naming corrections.
* Michael Starling <mstarling@logic.bm>
Wind direction naming corrections.
* Hans Einar Nielssen <hans.einar@nielssen.com>
Wind direction naming corrections.
* Nathan Neulinger <nneul@umr.edu>
Lots of enhancements and corrections. Too many to list here.