NAME

Geo::WeatherNOAA - Perl extension for interpreting the NOAA weather data

SYNOPSIS

  use Geo::WeatherNOAA;
  ($date,$warnings,$forecast,$coverage) = 
     process_city_zone('newport','ri','','get');

  foreach $key (keys %$forecast) {
        print "$key: $forecast->{$key}\n";
  }
  
  print process_city_hourly('newport news', 'va', '', 'get');

or

  use Geo::WeatherNOAA;
  print print_forecast('newport news','va');

DESCRIPTION

This module is intended to interpret the NOAA zone forecasts and current city hourly data files. It should give a programmer an easy time to use the data instead of having to mine it.

Be aware that if the variable $main::opt_v is set to anything (other than zero or '') then Geo::WeatherNOAA will be verbose on what it's doing with messages sent to STDERR. Useful for debugging.

REQUIRES

• Tie::IxHash

• LWP::Simple

• LWP::UserAgent

• Text::Wrap

FUNCTIONS

• print_forecast(CITY,STATE,FILENAME,FILEOPT,LWP_UserAgent)

  Returns text of the forecast

• print_current(CITY,STATE,FILENAME,FILEOPT,LWP_UserAgent)

  Returns text of current weather

• make_noaa_table(CITY,STATE,FILENAME,FILEOPT,LWP_UserAgent, MaxItems)

  This call gives the basic html table with current data and forecast for the next four periods ("tonight", "tomorrow","tomorrow night","day after") and warnings in an (I think) attractive, easy to read way.

  Max Items is a way to limit the number of items in the table returned... I think it looks best with no more than 4...5 gets crowded looking.

• process_city_hourly(CITY,STATE,FILENAME,FILEOPT,LWP_UserAgent)

  FILENAME is the file read from with FILEOPT "usefile" and written to if FILEOPT is "save"

  FILEOPT can be one of the following

          - save
                  will get and save the data to FILENAME
          - get
                  will retrieve new data (not store it)
          - usefile
                  will not retrieve data from URL, 
                  use FILENAME for data

  The fifth argument is for a user created LWP::UserAgent(3) which can be configured to work with firewalls. See the LWP::UserAgent(3) manpage for specific instructions. A basic example is like this:

     my $ua = new LWP::UserAgent;
     $ua->proxy(['http', 'ftp'], 'http://proxy.my.net:8080/');

  NOTE: You may also set the environment variable <CODE>http_proxy</CODE> and the auto-generated LWP::UserAgent will use LWP::UserAgent::env_proxy(). See LWP::UserAgent for more details.

• process_city_zone(CITY,STATE,FILENAME,FILEOPT,LWP_UserAgent)

  Call CITY, STATE, FILENAME (explained above), FILEOPT(explained above), and UserAgent (Explained above).

  The return is a three element list containing a) a string of the date/time of the forecast, b) a reference to the list of warnings (if any), and c) a reference to the hash of forecast. I recommend calling it like this:

      ($date, $warnings, $forecast, $coverage) = 
          process_city_zone('newport news','va',
          '/tmp/va_zone.html', 'save');

  Explanation of this call, it returns:

          $date
          - Scalar of the date of the forecast
  
          $warnings
          - Reference to the warnings list
          - EXAMPLE:
            foreach (@$warnings) { print; }
          
          $forecast
          - Reference to the forecast KEY, VALUE pairs
          - EXAMPLE:
            foreach $key (keys %$forecast) {
                  print "$key: $forecast->{$key}\n";
            }
  
          $coverage
          - Scalar of the coverage area of the forecast

• get_city_zone(CITY,STATE,FILENAME,FILEOPT,LWP_UserAgent)

  This sub is to get the block of data from the data source, which is chosen with the FILEOPTswitch.

• get_city_hourly(CITY,STATE,FILENAME,FILEOPT,LWP_UserAgent)

  This function gets the current weather from the data source, which is decided from FILEOPT(explained above). Input is CITY, STATE, FILENAME (filename to read/write from if FILEOPTis "get" or "usefile"), and UserAgent.

  This function returns a reference to a hash containing the data. It

  Same FILEOPTand LWP_UserAgent from above, and process the current weather data into an english sentence.

AUTHOR

Mark Solomon

msolomon@seva.net

http://www.seva.net/~msolomon/

SEE ALSO

perl(1), Tie::IxHash(3), LWP::Simple(3), LWP::UserAgent(3).