如何在地质层覆盖后盖上纵横比？

Question

我正在尝试将一些城市覆盖在地图之上。

import pandas as pd
import geopandas as gdp
import matplotlib.pyplot as plt
from shapely.geometry import box

destinations = ["Oslo", "Bergen", "Trondheim", "Tromsø", "Nordkapp", "Bodø", "Lofoten"]
world = gdp.read_file(gdp.datasets.get_path('naturalearth_lowres'))
norway = world[world.name=="Norway"]
norway =gdp.clip(norway, box(0, 0, 60,75)) # removing Svalbard
cities = world = gdp.read_file(gdp.datasets.get_path('naturalearth_cities'))
df = pd.read_csv("norway_cities.csv", sep=";")
norway_cities = gdp.GeoDataFrame(df, geometry=gdp.points_from_xy(df.lng, df.lat))

ax = norway.plot(color='white', edgecolor='black')
ax = cities[cities.name=="Stockholm"].plot(ax=ax, color='red')
ax = norway_cities[norway_cities.city.isin(destinations)].plot(ax=ax, color='blue')
plt.show()

当我绘制斯德哥尔摩坐标时，比例会受益：

当我绘制其余内容时，事情会扭曲：

来自不同的来源

数据 =“ https://i.sstatic.net/7ea4i.png” rel =“ nofollow noreferrer”>

更改图的大小不会影响结果，我如何保持第一张图片的相同纵横比？

Answer 1

构建 norway_cities 时，您尚未定义CRS。

norway_cities = gdp.GeoDataFrame(
    df, geometry=gdp.points_from_xy(df.lng, df.lat), crs="epsg:4386"
)

完整代码

• 从网页获取城市，因为我无法访问您的csv

import pandas as pd
import geopandas as gdp
import matplotlib.pyplot as plt
from shapely.geometry import box
import requests, io

destinations = ["Oslo", "Bergen", "Trondheim", "Tromsø", "Nordkapp", "Bodø", "Lofoten"]
world = gdp.read_file(gdp.datasets.get_path("naturalearth_lowres"))
norway = world[world.name == "Norway"]
norway = gdp.clip(norway, box(0, 0, 60, 75))  # removing Svalbard
cities = world = gdp.read_file(gdp.datasets.get_path("naturalearth_cities"))
# df = pd.read_csv("norway_cities.csv", sep=";")
df = pd.read_csv(
    io.StringIO(
        requests.get("https://simplemaps.com/static/data/country-cities/no/no.csv").text
    )
)
norway_cities = gdp.GeoDataFrame(
    df, geometry=gdp.points_from_xy(df.lng, df.lat), crs="epsg:4386"
)

ax = norway.plot(color="white", edgecolor="black")
ax = cities[cities.name == "Stockholm"].plot(ax=ax, color="red")
ax = norway_cities[norway_cities.city.isin(destinations)].plot(ax=ax, color="blue")
plt.show()