Folium is a useful library for visualization of maps. Here we see a visualization of the distribution of taxi pickups for a certain day at 5pm in Manhattan. I’ve been using Folium for my research work. Stay tuned for more examples in the future…
Basic map:
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# Build the default map for a specific location
map_osm = folium.Map(location=[40.7, -74.0], zoom_start=12)
map_osm
We must first center the map:
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top_left = [-73.973205, 40.806470]
bottom_left = [-74.035690, 40.709729]
bottom_right = [-73.992431, 40.696715]
top_right = [-73.934066, 40.781518]
polyNY_shapely = Polygon([(top_left), (bottom_left), (bottom_right), (top_right)])
g1 = wkt.loads(polyNY_shapely.wkt)
g2a = geojson.Feature(geometry=g1)
# Center the map
map_osm = folium.Map(location=[40.7, -74.0], zoom_start=12)
...
# Gather lat/lon data and their weights.
data = list(zip(lat, long, weight))
hm = HeatMap(data,
gradient={0.1: 'blue', 0.3: 'lime', 0.5: 'yellow', 0.7: 'orange', 1: 'red'},
min_opacity=0.05,
max_opacity=0.9,
max_amount=max(weight),
use_local_extrema=False)
# Add the heatmap
map_osm.add_child(hm)
We can add a slider with and update the map on a triggered event:
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slider_w = pn.widgets.IntSlider(name="Index", start=0, end=N-1)
pn.Column(slider_w, folium_pane, width=500).servable()
