如何在 Python 中使用 Geopandas 更改 crs 投影？

Question

我正在尝试将 the.crs 从圆柱投影（WGS84（纬度/经度））更改为墨卡托投影。 一些信息可以在这里找到（ https://geopandas.org/projections.html ）。 但是，对于比利时的这个 shapefile，它似乎对我不起作用。 （世界geopandas网站上的示例运行良好，因此所有库都已正确安装）有人知道问题可能是什么吗？ -> My.crs 保持圆柱形，不会更改为比利时的这个 shapefile 的墨卡托投影。 （数据集'BELGIUM__Municipalities.shp'-> https://hub.arcgis.com/datasets/esribeluxdata::belgium-municipalities-1 ）

示例代码：

import geopandas
import fiona
import matplotlib.pyplot as plt
import pandas as pd

def records(filename, list):
    list = sorted(list)
    with fiona.open(filename) as source: 
        for i, feature in enumerate(sourceô:max(list)+1):
            if i in list:
                yield feature

a = list(range(588))
municipalities = geopandas.GeoDataFrame.from_features(records("BELGIUM__Municipalities.shp",a))

municipalities.crs = "epsg:4326"  #WGS84(lat/lon)-projection
municipalities.plot(facecolor = 'lightgrey', linewidth = 0.05, edgecolor = 'black', alpha = 0.25)

municipalities.to_crs("epsg:3395") #Mercator-projection
municipalities.plot(facecolor = 'lightgrey', linewidth = 0.05, edgecolor = 'black', alpha = 0.25)

plt.show()

编辑：

import geopandas
import fiona
import matplotlib.pyplot as plt
import pandas as pd

def records(filename, list):
    list = sorted(list)
    with fiona.open(filename) as source: 
        for i, feature in enumerate(sourceô:max(list)+1):
            if i in list:
                yield feature

a = list(range(588))
municipalities = geopandas.GeoDataFrame.from_features(records("BELGIUM__Municipalities.shp",a))

municipalities.crs = "epsg:4326"  #WGS84(lat/lon)-projection
municipalities.plot(facecolor = 'lightgrey', linewidth = 0.05, edgecolor = 'black', alpha = 0.25)

municipalities = municipalities.to_crs("epsg:3395") #Mercator-projection
municipalities.plot(facecolor = 'lightgrey', linewidth = 0.05, edgecolor = 'black', alpha = 0.25)

plt.show()

Answer 1

GeoDataFrame.to_crs()不会就地重新投影，它会返回一个新的 object。 如果您想像这样使用您的代码，您必须将其分配回municipalities 。

municipalities = municipalities.to_crs("epsg:3395") #Mercator-projection

最重要的是，您的绘图代码将不起作用，正确的语法是：

municipalities.plot(facecolor = 'lightgrey', linewidth = 0.05, edgecolor = 'black', alpha = 0.25)

注意. 而不是,在数字上。