15 lines
505 B
JavaScript
15 lines
505 B
JavaScript
export function getDistance(lat1, lon1, lat2, lon2) {
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const R = 6371e3; // metres
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const φ1 = (lat1 * Math.PI) / 180; // φ, λ in radians
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const φ2 = (lat2 * Math.PI) / 180;
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const Δφ = ((lat2 - lat1) * Math.PI) / 180;
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const Δλ = ((lon2 - lon1) * Math.PI) / 180;
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const a =
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Math.sin(Δφ / 2) * Math.sin(Δφ / 2) +
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Math.cos(φ1) * Math.cos(φ2) * Math.sin(Δλ / 2) * Math.sin(Δλ / 2);
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const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
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return R * c; // in metres
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}
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