mapbox / mapboxgl-jupyter

Use Mapbox GL JS to visualize data in a Python Jupyter notebook
MIT License
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viz.create_html() rounds lat/lng to 4 decimal places which drops accuracy to 11m #185

Open aidanlister opened 3 years ago

aidanlister commented 3 years ago

This is the difference between this:

Screen Shot 2021-05-31 at 3 37 04 pm

And this:

Screen Shot 2021-05-31 at 3 38 20 pm

This is happening here: https://github.com/mapbox/mapboxgl-jupyter/blob/9a15a0759db5b0c5dc8d59f4a8e0d77b9c378daf/mapboxgl/viz.py#L281

I'm attempting to solve this by passing in a decimal rather than a float when building my FeatureCollection:

    features.append(Feature(
        geometry=Point((Decimal(m['lng']), Decimal(m['lat']))),
    ))

You can monkey patch this like this:

import json
import decimal

class FullJSONEncoder(json.JSONEncoder):
    def default(self, o):
        if isinstance(o, decimal.Decimal):
            return str(o)
        return super().default(o)

default_props = {'cls': FullJSONEncoder, 'skipkeys': False, 'check_circular': False, 'allow_nan': False, 'indent': False, 'separators': None, 'default': None, 'sort_keys': False, 'ensure_ascii': False}
with patch.object(json.dumps, '__kwdefaults__', default_props):
    ...