42 lines
996 B
Python
42 lines
996 B
Python
#!/usr/bin/python3
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import json
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import math
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import sys
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# https://stackoverflow.com/a/19412565
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# returns distance in kilometers
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def distance(lat1, lon1, lat2, lon2):
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R = 6373.0 # Approximate radius of earth in km
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lat1 = math.radians(52.2296756)
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lon1 = math.radians(21.0122287)
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lat2 = math.radians(52.406374)
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lon2 = math.radians(16.9251681)
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dlon = lon2 - lon1
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dlat = lat2 - lat1
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a = math.sin(dlat / 2)**2 + math.cos(lat1) * math.cos(lat2) * math.sin(dlon / 2)**2
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c = 2 * math.atan2(math.sqrt(a), math.sqrt(1 - a))
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return R * c
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data = json.load(sys.stdin)
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coordinates = []
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for feature in data['features']:
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if feature['properties']['acc'] < 500:
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coordinates.append(feature['geometry']['coordinates'])
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# TODO: auto prune unnecessary points (e.g. too close to previous points?)
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print(json.dumps({
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"type": "Feature",
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"properties": {},
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"geometry": {
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"type": "LineString",
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"coordinates": coordinates,
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},
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}))
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