axes
设置一致的配色方案?以下应该是一个完全可重现的示例,用于运行代码并获得与我在下面发布的相同的数字。
从国家统计局获取 shapefile 数据。在终端中将其作为
bash
文件/命令运行。
wget --output-document 'LA_authorities_boundaries.zip' 'https://opendata.arcgis.com/datasets/8edafbe3276d4b56aec60991cbddda50_1.zip?outSR=%7B%22latestWkid%22%3A27700%2C%22wkid%22%3A27700%7D&session=850489311.1553456889'
mkdir LA_authorities_boundaries
cd LA_authorities_boundaries
unzip ../LA_authorities_boundaries.zip
读取 shapefile 并创建一个虚拟
GeoDataFrame
用于重现行为的 Python 代码。
import geopandas as gpd
import pandas as pd
import matplotlib.pyplot as plt
gdf = gpd.read_file(
'LA_authorities_boundaries/Local_Authority_Districts_December_2015_Full_Extent_Boundaries_in_Great_Britain.shp'
)
# 380 values
df = pd.DataFrame([])
df['AREA_CODE'] = gdf.lad15cd.values
df['central_pop'] = np.random.normal(30, 15, size=(len(gdf.lad15cd.values)))
df['low_pop'] = np.random.normal(10, 15, size=(len(gdf.lad15cd.values)))
df['high_pop'] = np.random.normal(50, 15, size=(len(gdf.lad15cd.values)))
加入来自 ONS 的 shapefile 并创建一个
geopandas.GeoDataFrame
def join_df_to_shp(pd_df, gpd_gdf):
""""""
df_ = pd.merge(pd_df, gpd_gdf[['lad15cd','geometry']], left_on='AREA_CODE', right_on='lad15cd', how='left')
# DROP the NI counties
df_ = df_.dropna(subset=['geometry'])
# convert back to a geopandas object (for ease of plotting etc.)
crs = {'init': 'epsg:4326'}
gdf_ = gpd.GeoDataFrame(df_, crs=crs, geometry='geometry')
# remove the extra area_code column joined from gdf
gdf_.drop('lad15cd',axis=1, inplace=True)
return gdf_
pop_gdf = join_df_to_shp(df, gdf)
绘制图
fig,(ax1,ax2,ax3,) = plt.subplots(1,3,figsize=(15,6))
pop_gdf.plot(
column='low_pop', ax=ax1, legend=True, scheme='quantiles', cmap='OrRd',
)
pop_gdf.plot(
column='central_pop', ax=ax2, legend=True, scheme='quantiles', cmap='OrRd',
)
pop_gdf.plot(
column='high_pop', ax=ax3, legend=True, scheme='quantiles', cmap='OrRd',
)
for ax in (ax1,ax2,ax3,):
ax.axis('off')
ax
对象共享相同的容器(最好是 central_pop
场景 quantiles
),以便整个图形的图例保持一致。一个场景(中央)的 quantiles
将成为所有场景的 levels
这样我应该在最右侧看到较深的颜色(更红)
ax
,显示high_pop
场景。
如何为整个图形/每个
ax
对象设置颜色方案箱?
我能看到这个工作的最简单的方法是 a) 为
geopandas.plot()
函数提供一组 bin
b) 从一个ax
中提取颜色方案/箱并将其应用到另一个。
从 geopandas 0.5 开始,您可以使用定义为
scheme="User_Defined"
的自定义方案,并通过 classification_kwds
提供分箱。
import geopandas as gpd
print(gpd.__version__) ## 0.5
import numpy as np; np.random.seed(42)
import matplotlib.pyplot as plt
gdf = gpd.read_file(gpd.datasets.get_path('naturalearth_lowres'))
gdf['quant']=np.random.rand(len(gdf))*100-20
fig, ax = plt.subplots()
gdf.plot(column='quant', cmap='RdBu', scheme="User_Defined",
legend=True, classification_kwds=dict(bins=[-10,20,30,50,70]),
ax=ax)
plt.show()
因此剩下的任务是从其中一列的分位数中获取 bin 列表。这应该很容易完成,例如通过
import mapclassify
bins = mapclassify.Quantiles(gdf['quant'], k=5).bins
然后在上面的代码中设置
classification_kwds=dict(bins=bins)
。
您也可以尝试下面的解决方案(注意Cluster_As_Text是字符串类型):
import matplotlib.pyplot as plt
import geopandas as gpd
import matplotlib.colors as colors
# Define color dictionary for clusters
color_dict = {'0': 'green', '1': 'yellow', '2': 'red'}
# Add more colours as needed
# Create a figure and axis
fig, ax = plt.subplots(figsize=(15, 10))
# Plot GeoDataFrame, coloring by 'Cluster_As_Text' column
merged.plot(ax=ax, column="Cluster_As_Text", legend=True,
cmap=colors.ListedColormap(list(color_dict.values())))
# Customize legend position and appearance
legend = ax.get_legend()
legend.set_title('Cluster')
legend.set_bbox_to_anchor((0.25, 0.96)) # Adjust position of legend
# Show plot
plt.show()
获得如下输出: