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Geo::Distance::XS(3pm) User Contributed Perl Documentation Geo::Distance::XS(3pm) NAME
Geo::Distance::XS - speed up Geo::Distance SYNOPSIS
use Geo::Distance::XS; my $geo = Geo::Distance->new; my $distance = $geo->distance(mile => $lon1, $lat1 => $lon2, $lat2); DESCRIPTION
The "Geo::Distance::XS" module provides faster C implementations of the distance calculations found in "Geo::Distance". See the documentation for that module for usage. NOTE: As of version 0.13, Geo::Distance automatically uses this module if it is installed. FORMULAS
In addition to the formulas offered in "Geo::Distance", this module implements the additional formulas: alt: Andoyer-Lambert-Thomas Formula This is faster than the Vincenty formula, but trades a bit of accuracy. PERFORMANCE
This distribution contains a benchmarking script which compares "Geo::Distance::XS" with "Geo::Distance" and "GIS::Distance::Fast". These are the results on a MacBook 2GHz with Perl 5.14.2: ---- [ Formula: hsin ] ------------------------------------ perl - distance from LA to NY: 2443.08796228363 miles xs - distance from LA to NY: 2443.08796228363 miles gis_fast - distance from LA to NY: 2443.08796228363 miles Rate gis_fast perl xs gis_fast 24802/s -- -70% -98% perl 81919/s 230% -- -92% xs 1003704/s 3947% 1125% -- ---- [ Formula: tv ] ------------------------------------ perl - distance from LA to NY: 2448.24135235512 miles xs - distance from LA to NY: 2448.2413523656 miles gis_fast - distance from LA to NY: 2448.24135235512 miles Rate perl gis_fast xs perl 18101/s -- -19% -95% gis_fast 22330/s 23% -- -94% xs 345717/s 1810% 1448% -- ---- [ Formula: polar ] ------------------------------------ perl - distance from LA to NY: 2766.02509696782 miles xs - distance from LA to NY: 2766.02509696782 miles gis_fast - distance from LA to NY: 2766.02509696782 miles Rate gis_fast perl xs gis_fast 19200/s -- -78% -98% perl 87682/s 357% -- -93% xs 1214700/s 6227% 1285% -- ---- [ Formula: cos ] ------------------------------------ perl - distance from LA to NY: 2443.08796228363 miles xs - distance from LA to NY: 2443.08796228363 miles gis_fast - distance from LA to NY: 2443.08796228363 miles Rate gis_fast perl xs gis_fast 24435/s -- -69% -98% perl 78913/s 223% -- -93% xs 1147836/s 4597% 1355% -- ---- [ Formula: gcd ] ------------------------------------ perl - distance from LA to NY: 2443.08796228363 miles xs - distance from LA to NY: 2443.08796228363 miles gis_fast - distance from LA to NY: 2443.08796228363 miles Rate gis_fast perl xs gis_fast 18270/s -- -75% -98% perl 74472/s 308% -- -93% xs 1102769/s 5936% 1381% -- ---- [ Formula: mt ] ------------------------------------ perl - distance from LA to NY: 2443.08796228363 miles xs - distance from LA to NY: 2443.08796228363 miles gis_fast - distance from LA to NY: 2443.08796228363 miles Rate gis_fast perl xs gis_fast 17935/s -- -75% -98% perl 71739/s 300% -- -94% xs 1135525/s 6231% 1483% -- This distribution contains another benchmarking script which compares only the XS formulas over several different coordinates: Rate tv hsin alt cos mt gcd polar tv 16906/s -- -90% -90% -91% -91% -91% -92% hsin 165414/s 878% -- -4% -8% -10% -13% -17% alt 172032/s 918% 4% -- -5% -7% -9% -14% cos 180326/s 967% 9% 5% -- -2% -5% -10% mt 184357/s 991% 11% 7% 2% -- -3% -8% gcd 189253/s 1019% 14% 10% 5% 3% -- -6% polar 200386/s 1085% 21% 16% 11% 9% 6% -- Calculated length for short distance: alt : 40.3740136064528 miles cos : 40.3095459813536 miles gcd : 40.3095459813294 miles hsin : 40.3095459813294 miles mt : 40.3095459813536 miles polar: 46.7467797109043 miles tv : 40.3740136384531 miles Calculated length for long distance: alt : 2448.24135691376 miles cos : 2443.08796228363 miles gcd : 2443.08796228363 miles hsin : 2443.08796228363 miles mt : 2443.08796228363 miles polar: 2766.02509696782 miles tv : 2448.2413523656 miles Calculated length for nearly antipodes: alt : 12340.6455133245 miles cos : 12340.327635068 miles gcd : 12340.327635068 miles hsin : 12340.327635068 miles mt : 12340.327635068 miles polar: 12368.4764642469 miles tv : 12340.7483034002 miles Calculated length for antipodes: alt : 12429.86673988 miles cos : 219.005548031861 miles gcd : 12438.0476860875 miles hsin : 12438.0475680956 miles mt : 219.005548031861 miles polar: 12438.0476860875 miles tv : 12370.1885059814 miles Calculated length for polar antipodes: alt : 12429.86673988 miles cos : 12438.0476860875 miles gcd : 12438.0476860875 miles hsin : 12438.0476860875 miles mt : 12438.0476860875 miles polar: 12438.0476860875 miles tv : 12429.8667398787 miles SEE ALSO
Geo::Distance http://blogs.esri.com/esri/apl/2010/09/28/fast-times-at-geodesic-high/ <http://blogs.esri.com/esri/apl/2010/09/28/fast-times-at-geodesic- high/> REQUESTS AND BUGS
Please report any bugs or feature requests to http://rt.cpan.org/Public/Bug/Report.html?Queue=Geo-Distance-XS <http://rt.cpan.org/Public/Bug/Report.html?Queue=Geo-Distance-XS>. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes. SUPPORT
You can find documentation for this module with the perldoc command. perldoc Geo::Distance::XS You can also look for information at: o GitHub Source Repository http://github.com/gray/geo-distance-xs <http://github.com/gray/geo-distance-xs> o AnnoCPAN: Annotated CPAN documentation http://annocpan.org/dist/Geo-Distance-XS <http://annocpan.org/dist/Geo-Distance-XS> o CPAN Ratings http://cpanratings.perl.org/d/Geo-Distance-XS <http://cpanratings.perl.org/d/Geo-Distance-XS> o RT: CPAN's request tracker http://rt.cpan.org/Public/Dist/Display.html?Name=Geo-Distance-XS <http://rt.cpan.org/Public/Dist/Display.html?Name=Geo-Distance-XS> o Search CPAN http://search.cpan.org/dist/Geo-Distance-XS/ <http://search.cpan.org/dist/Geo-Distance-XS/> COPYRIGHT AND LICENSE
Copyright (C) 2009-2012 gray <gray at cpan.org>, all rights reserved. This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself. AUTHOR
gray, <gray at cpan.org> perl v5.14.2 2012-04-14 Geo::Distance::XS(3pm)
