NAME
METAR - Process routine aviation weather reports in the METAR format.
SYNOPSIS
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;DESCRIPTION
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.
USAGE
How you might use this
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://tgsv5.nws.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.
Functions
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 coverting 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()
-
PRIVATE
Called internally to break the METAR into its component tokens.
- _process()
-
PRIVATE
Used to make sense of the tokens found in _tokenize().
Variables
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.
- VERSION
-
The version of METAR.pm that you're using.
- METAR
-
The actual, raw METAR.
- TYPE
-
Report type: "METAR or SPECI".
- SITE
-
4-letter site code.
- DATE
-
The date on which the report was issued.
- TIME
-
The time at which the report was issued.
- MOD
-
Modifier (AUTO/COR) if any.
- WIND_DIR_ENG
-
The current wind direction in english (Southwest, East, North, etc.)
- WIND_DIR_DEG
-
The current wind direction in degrees.
- WIND_KTS
-
The current wind speed in Knots.
- WIND_MPH
-
The current wind speed in Miles Per Hour.
- WIND_KTS_GUST
-
The current wind gusting speed in Knots.
- WIND_MPH_GUST
-
The current wind gustin speed in Miles Per Hour.
- VISIBILITY
-
Visibility information.
- WIND
-
Wind information.
- RUNWAY
-
Runway information.
- WEATHER
-
Current weather.
- SKY
-
Current sky conditions.
- C_TEMP
-
Temperature in Celcius.
- F_TEMP
-
Temperature in Farenheit.
- C_DEW
-
Dew point in Celcius.
- F_DEW
-
Dew point in Farenheit.
- ALT
-
Altimeter setting (barometric pressure).
- REMARKS
-
Any remarks in the report.
NOTES
Test suite is small and incomplete. Needs work yet.
Older versions of this module were installed as "METAR" instaed of "Geo::METAR"
Adding a find() method.
I shoule 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.
BUGS
The only known bug was corrected in the latest release. Please report any bugs that you find.
AUHTOR AND COPYRIGHT
Copyright 1998-99, Jeremy D. Zawodny <jzawodn@wcnet.org>
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/