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Geo::Hash(3pm) User Contributed Perl Documentation Geo::Hash(3pm)

NAME

Geo::Hash - Encode / decode geohash.org locations.

VERSION

This document describes Geo::Hash version 0.02

SYNOPSIS

    use Geo::Hash;
    my $gh = Geo::Hash->new;
    my $hash = $gh->encode( $lat, $lon );
    my ( $lat, $lon ) = $gh->decode( $hash );

DESCRIPTION

Geohash is a latitude/longitude geocode system invented by Gustavo Niemeyer when writing the web service at geohash.org, and put into the public domain.

This module encodes and decodes geohash locations.

See <http://en.wikipedia.org/wiki/Geohash> and <http://geohash.org> for more information.

INTERFACE

"new"

Create a new Geo::Hash object.

    my $gh = Geo::Hash->new;

"precision"

Infer a suitable precision (number of character in hash) for a given lat, lon pair.

    my $prec = $gh->precision( $lat, $lon );

"encode"

Encode a lat, long pair into a geohash.

    my $hash = $gh->encode( $lat, $lon );

You may optionally supply the length of the desired geohash:

    # Very precise
    my $hash = $gh->encode( $lat, $lon, 10 );

If the precision argument is omitted "precision" will be used to provide a default.

"decode_to_interval"

Like "decode" but instead of returning a pair of coordinates returns the interval for each coordinate. This gives some indication of how precisely the original hash specified the location.

The return value is a pair of array refs. Each referred to array contains the upper and lower bounds for each coordinate.

    my ( $lat_range, $lon_range ) = $gh->decode_to_interval( $hash );
    # $lat_range and $lon_range are references to two element arrays

"decode"

Decode a geohash into a lat, long pair.

    my ( $lat, $lon ) = $gh->decode( $hash );

CONFIGURATION AND ENVIRONMENT

Geo::Hash requires no configuration files or environment variables.

DEPENDENCIES

None.

INCOMPATIBILITIES

None reported.

BUGS AND LIMITATIONS

No bugs have been reported.

Please report any bugs or feature requests to "bug-geo-hash@rt.cpan.org", or through the web interface at <http://rt.cpan.org>.

AUTHOR

Andy Armstrong "<andy@hexten.net>"

<http://geohash.org/gcwrdtsvrfgr>

LICENCE AND COPYRIGHT

Copyright (c) 2008, Andy Armstrong "<andy@hexten.net>".

This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.

2022-10-13 perl v5.34.0