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Converts the given string representation of WGS84 coordinates into a standard lat/lng object.
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/** | |
* Converts the given string representation of WGS84 coordinates into a standard lat/lng object. | |
* | |
* @example 60 deg 08.2151' N, 24 deg 25.6136' E | |
* @example 43°38'19.39"N,116°14'28.86"W | |
* @example +43.6387194°, -116.2413500° | |
* | |
* For convenience (and to avoid "Cannot read property 'lat' of undefined" errors), always returns an | |
* object with the aforementioned keys. For invalid input, the VALUES of the keys will be undefined. | |
* | |
* @returns https://developers.google.com/maps/documentation/javascript/reference#LatLngLiteral | |
* | |
* @link https://gist.github.com/jareware/083ecc072bab29130415 | |
* @author Jarno Rantanen <[email protected]> | |
* @license Do whatever you want with it | |
*/ | |
function parseWGS84String(input) { | |
return (typeof input === 'string' ? input : '0,0').replace(/deg/gi, '°').split(',').map(function(part) { | |
return (part.match(/([+-]?\d+(?:\.\d+)?\s*[°'"]|[nesw])+?/gi) || []).reduce(function(memo, component) { | |
var unit = component && component[component.length - 1].toUpperCase(); | |
var power = '°\'"'.indexOf(unit); | |
if (power >= 0) { | |
return (memo || 0) + parseFloat(component) / Math.pow(60, power); | |
} else if ('SW'.indexOf(unit) >= 0) { | |
return (memo || 0) * -1; | |
} | |
return memo; | |
}, null); | |
}).reduce(function(memo, part, index) { | |
memo[index ? 'lng' : 'lat'] = typeof part === 'number' ? part : undefined; | |
return memo; | |
}, { lat: undefined, lng: undefined }); | |
} | |
// UNIT TEST CODE: | |
[ | |
// Input to function: // Expected output: | |
[ "60 deg 08.2151' N, 24 deg 25.6136' E", { lat: 60.136918333333334, lng: 24.426893333333332 } ], | |
[ "60° 08.2151' N, 24° 25.6136' E", { lat: 60.136918333333334, lng: 24.426893333333332 } ], | |
[ "43°38'19.39\"N, 116°14'28.86\"W", { lat: 43.63871944444445, lng: -116.2413500 } ], | |
[ "37° 26' 56.74\" N, 126° 27' 9.05\" E", { lat: 37.44909444444444, lng: 126.45251388888889 } ], | |
[ "+43.6387194°, -116.2413500°", { lat: 43.6387194, lng: -116.2413500 } ], | |
[ "0°, 0°", { lat: 0, lng: 0 } ], | |
[ "0, 0", { lat: undefined, lng: undefined } ], | |
[ "bla°, bla°", { lat: undefined, lng: undefined } ], | |
[ "bla", { lat: undefined, lng: undefined } ], | |
[ "", { lat: undefined, lng: undefined } ], | |
[ false, { lat: undefined, lng: undefined } ], | |
[ {}, { lat: undefined, lng: undefined } ], | |
// Oracle: http://www.earthpoint.us/convert.aspx | |
].forEach(function(tuple) { | |
var output = parseWGS84String(tuple[0]); | |
if (output.lat !== tuple[1].lat || output.lng !== tuple[1].lng) { | |
console.log('FAIL:', JSON.stringify({ | |
input: tuple[0], | |
expected: tuple[1], | |
actual: output | |
}, undefined, 4)); | |
} else { | |
console.log('OK:', tuple[0], '=>', output); | |
} | |
}); |
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