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

💖 GIS::Distance::MathTrig — the perl one 🫶

okay so bestie, we're looking at GIS::Distance::MathTrig(3pm) from the User Contributed Perl Documentation collection, and honestly? it's giving ✨ trigonometry but make it cute ✨. it's the manpage for the MathTrig formula class in the GIS::Distance family. let's get into it 💅

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✨ NAME ✨

GIS::Distance::MathTrig — great circle distance calculations using Math::Trig. 🌍

(no cap, it does exactly what it says on the tin, we love a self-aware module)

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🌸 DESCRIPTION 🌸

so this formula uses Math::Trig's great_circle_distance() function, right? and at this time — like, currently, as of this writing — that function uses math that's almost exactly the same formula as the GIS::Distance::Cosine formula. 😭 they're basically twins.

and here's the tea: the Cosine formula is about 5% faster than this formula. 💀 so if you're picking between them... that's a thing you now know. iykyk.

normally, bestie, you do not use this module directly. 🙈 instead you use GIS::Distance, which in turn interfaces with the various formula classes for you. it's the main character, this is the supporting cast. 👑

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🧚 FORMULA 🧚

here's the math, verbatim, no notes:

lat0 = 90 degrees - phi0
lat1 = 90 degrees - phi1
d = R * arccos(cos(lat0) * cos(lat1) * cos(lon1 - lon01) + sin(lat0) * sin(lat1))

as stated in the Math::Trig documentation. 📚 slay.

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🫶 SUPPORT 🫶

see "SUPPORT" in GIS::Distance. that's where the help lives, go look there 💖

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👑 AUTHORS 👑

see "AUTHORS" in GIS::Distance. the legends are credited over there ✨

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🎀 LICENSE 🎀

see "LICENSE" in GIS::Distance. legal stuff, very demure, very mindful 🌸

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and that's the whole page, bestie!! it shipped with perl v5.36.0 and the date on it is 2023-10-21 — so it's got a lil vintage moment going on. anyway, go calculate some great circle distances, you absolute icon 💅💖✨