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Latitude Longitude Distance - 140byt.es

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LICENSE.txt
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DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
Version 2, December 2004
 
Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>
 
Everyone is permitted to copy and distribute verbatim or modified
copies of this license document, and changing it is allowed as long
as the name is changed.
 
DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
 
0. You just DO WHAT THE FUCK YOU WANT TO.
README.md
Markdown

Game of Life - 140byt.es

This uses the Haversine formula to calculate the great-circle distance between two points.

Usage

distanceLatLng (
  latitude1, longitude1 // first coordinates
  latitude2, longitude2 // seconds coordinates
  diameter // earth diameter (might be any unit)
)

// returns the distance in the specified unit

Earth Diameter

  • 2 * 6378.137 Kilometers
  • 2 * 6378137 Meter
  • 2 * 3963.190 Miles

Author

Created by Martin Kleppe (@aemkei) at Ubilabs.

For more information

See the 140byt.es site for a showcase of entries (built itself using 140-byte entries!), and follow @140bytes on Twitter.

annotated.js
JavaScript
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function(
a, b, // first coord
c, d, // second coord
e, // earth diameter (might be any unit)
z, i // placeholder
){
with (Math) { // use "Math" in context
z = PI / 360; // used to convert in radiants
return e * atan2(
sqrt(
i = pow(sin((c-a)*z), 2) +
cos(a*z*2) * cos(c*z*2) *
pow(sin((d-b)*z), 2)
),
sqrt(1-i)
);
}
}
package.json
JSON
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{
"name": "distanceLatLng",
 
"description": "Calculate distance between Latitude/Longitude points.",
 
"keywords": [
"geo",
"maps",
"distance"
]
}
test.html
HTML
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<!DOCTYPE html>
<title>Distance between Latitude/Longitude points </title>
<h4>Distance Hamburg-Tokyo</h4>
<div><b>8986</b> km expected</div>
<div><b id="km"></b> km calculated</div>
<div><b>5584</b> miles expected</div>
<div><b id="miles"></b> miles calculated</div>
 
<script>
var distance = function(a,b,c,d,e,z,i){with(Math)return z=PI/360,e*atan2(sqrt(i=pow(sin((c-a)*z),2)+cos(a*z*2)*cos(c*z*2)*pow(sin((d-b)*z),2)),sqrt(1-i))},
DIAMETER_IN_KM = 2 * 6378.137,
DIAMETER_IN_MILES = 2 * 3963.190,
hamburg = { lat: 53.562, lng: 9.994 },
tokyo = { lat: 35.691, lng: 139.691 };
document.getElementById( "km" ).innerHTML = Math.round(
distance(
hamburg.lat, hamburg.lng,
tokyo.lat, tokyo.lng,
DIAMETER_IN_KM
)
);
document.getElementById( "miles" ).innerHTML = Math.round(
distance(
hamburg.lat, hamburg.lng,
tokyo.lat, tokyo.lng,
DIAMETER_IN_MILES
)
);
</script>

Great job! Flawless stereometry packed into tweet.

The only one suggestion, as the assignment has very low precedence we may re-use z variable instead of i

function(a,b,c,d,e,z){with(Math)return z=PI/360,e*atan2(sqrt(z=pow(sin((c-a)*z),2)+cos(a*z*2)*cos(c*z*2)*pow(sin((d-b)*z),2)),sqrt(1-z))}

Thanks for that suggestion. It saved another 2 bytes!

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