1GIS::Distance::GreatCirUcsleer(3Cpomn)tributed Perl DocuGmIeSn:t:aDtiisotnance::GreatCircle(3pm)
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6 GIS::Distance::GreatCircle - Great circle distance calculations.
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9 A true Great Circle Distance calculation. This was created because the
10 GIS::Distance::MathTrig formula uses Math::Trig's
11 "great_circle_distance()" which doesn't actually appear to use the
12 actual Great Circle Distance formula (more likely Cosine).
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14 A faster (XS) version of this formula is available as
15 GIS::Distance::Fast::GreatCircle.
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17 Normally this module is not used directly. Instead GIS::Distance is
18 used which in turn interfaces with the various formula classes.
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21 c = 2 * asin( sqrt(
22 ( sin(( lat1 - lat2 )/2) )**2 +
23 cos( lat1 ) * cos( lat2 ) *
24 ( sin(( lon1 - lon2 )/2) )**2
25 ) )
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28 See "SUPPORT" in GIS::Distance.
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31 See "AUTHORS" in GIS::Distance.
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34 See "LICENSE" in GIS::Distance.
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38perl v5.36.0 2022-07-22 GIS::Distance::GreatCircle(3pm)