GIS::D...Circle(3pm)

✨ GIS::Distance::GreatCircle ✨

okay bestie, welcome to the GIS::Distance::GreatCircle page from the Perl docs (manual section 3pm) 💖 this is the one that does great circle distance calculations, and it is lowkey iconic for reasons we're about to get into.

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🎀 NAME 🎀

GIS::Distance::GreatCircle — great circle distance calculations. that's it, that's the whole vibe 💅

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🌸 DESCRIPTION 🌸

So like, this is a true Great Circle Distance calculation. fr fr. not the fake one.

The tea is: this module got created because GIS::Distance::MathTrig uses Math::Trig's great_circle_distance() — and that thing doesn't actually appear to use the actual Great Circle Distance formula 😭 (it's more likely Cosine, ngl). so we made our own. main character move honestly.

There's also a faster (XS) version of this formula if you want that speed, and it lives at GIS::Distance::Fast::GreatCircle 🔥

Also important: normally you do not use this module directly. instead you use GIS::Distance, which in turn interfaces with the various formula classes. she's the manager, this module is the talent ✨

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🦋 FORMULA 🦋

here's the math, and yes she ate:

c = 2 * asin( sqrt(
    ( sin(( lat1 - lat2 )/2) )**2 +
    cos( lat1 ) * cos( lat2 ) *
    ( sin(( lon1 - lon2 )/2) )**2
) )

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💜 SUPPORT 💜

See "SUPPORT" in GIS::Distance.

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👑 AUTHORS 👑

See "AUTHORS" in GIS::Distance.

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🌈 LICENSE 🌈

See "LICENSE" in GIS::Distance.

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no cap, everything above is exactly what the page says — I just made it cute 🫶

and that's the whole page bestie, periodt 💅✨

this was perl v5.36.0, dated 2023-10-21, and it's giving GIS::D...Circle(3pm) energy 🎀🦋 bye ily, go calculate some distances 💖