Folium Chropleth Map呈现灰色阴影，而不是主题图的真实颜色

Question

我遇到一个问题，我的Choropleth贴图无法正确渲染。

[我有很多关于芝加哥市的乘车信息，我想按人口普查图创建一个choropleth地图。我检查了geojson文件中的key_on功能是否为“ geoid10”，并确保拾取人口普查记录全部匹配。

我还确保geojson文件和数据框中的键的数据类型相同（它们都是对象）

不过，我的拟声曲谱图呈现的是黑色/灰色调，而不是正确调调的图谱。

这是我的代码：

# Import packages
import pandas as pd
import geopandas as gpd
import folium

# Load in GeoJSON file, because works with Folium
geosjon_file = "Boundaries - Census Tracts - 2010.geojson"
chicago_census_tracts = gpd.read_file(geosjon_file)

# Pickup by census tract
pickup_by_censustract = pd.read_csv("pickup_demand_by_censustract_test.csv")

# Convert Pickup Census Tract to dtype: object, as key_on object in geosjon_file is also an dtype: object
pickup_by_censustract["Pickup Census Tract"].astype(str)

# Creating Chicago map with Folium
chicago_map = folium.Map(
    location=[41.881832, -87.623177],
    zoom_start=9)
#folium.TileLayer("CartoDB positron", name="Light Map", control=False).add_to(chicago_map)

# Overlaying Chicago map with bounderies of census tracts
folium.GeoJson(chicago_census_tracts).add_to(chicago_map)

# Creating Choropleth
folium.Choropleth(
    geo_data=chicago_census_tracts,
    name="choropleth",
    data=pickup_by_censustract,
    columns=["Pickup Census Tract", "Count"],
    key_on="feature.properties.geoid10",
    fill_color="YlGn",
    fill_opacity=0.7,
    line_opacity=0.2,
    legend_name="Ride-hailing demand"
).add_to(chicago_map)

folium.LayerControl().add_to(chicago_map)
chicago_map

这是Jupyter笔记本中的当前输出：

尽管我相信我已将key_on功能与​​数据框正确匹配，但我仍然认为问题仍然在于将geojson文件与数据框正确匹配。

请在此处找到代码，数据和geojson文件：https://github.com/Doncorleone1018/Chicago-choropleth

• 当前python版本：3.7.4
• 当前文件版本：0.10.1

Answer 1

只需更改此行：

pickup_by_censustract["Pickup Census Tract"].astype(str)

进入：

pickup_by_censustract["Pickup Census Tract"] = pickup_by_censustract["Pickup Census Tract"].astype(str)