Osmnx：如何使 plot_shape() 在 pyplot 子图中工作？

Question

我一直在使用 OSMNX 从 Open Street Maps 中提取公园的形状。我试图将它们显示为标准的 pyplot 子图，但我不能让它直接工作。

假设这是我的位置数组：

places = 
     {'Hyde Park'       : 'Hyde Park, London, UK',
      'Kensington Gardens'        : 'Kensington Gardens, London, UK',
      'Regents Park'       : 'Regents Park, London, UK',
      'Hampstead Heath' : 'Hampstead Heath, London, UK',
      'Alexandra Park' : 'Alexandra Park, London, UK',
      'Clissold Park' : 'Clissold Park, London, UK',
      'Finsbury Park' : 'Finsbury Park, N4 2NQ, London, UK',
      'Russell Square' : 'Russell Square, London, UK'
     }

以下正确显示堆叠的形状：

for place in sorted(places.keys()):
    query = places[place]
    print(query)
    G = ox.gdf_from_place(query)
    fig, ax = ox.plot_shape(G)

我不是 pyplot/OSMNX 的专家，但我的理解是，为了将形状图传递给子图，我需要以某种方式 "extract the axes"。

但是，我知道如何获取形状，将其转换为 shapefile，并在子图中显示：

import shapefile
n = len(places)
ncols = int(np.ceil(np.sqrt(n)))
nrows = int(np.ceil(n / ncols))
figsize = (ncols * 3, nrows * 3)

fig, axes = plt.subplots(nrows, ncols, figsize=figsize, subplot_kw, {'projection':None})
axes = [item for sublist in axes for item in sublist]

for ax, place in zip(axes, sorted(places.keys())):
    query = places[place]
    G = ox.gdf_from_place(query)
    ox.save_gdf_shapefile(G, folder='shp', filename=place)

    shp = shapefile.Reader("shp/"+place+"/"+place+".shp")

    for shape in shp.shapeRecords():
        x = [i[0] for i in shape.shape.points[:]]
        y = [i[1] for i in shape.shape.points[:]]
        ax.plot(x,y)

是否可以直接使用 plot_shape() 生成相同的图表？

Answer 1

几个选项，具体取决于您的最终目标：

import osmnx as ox
import matplotlib.pyplot as plt
ox.config(use_cache=True, log_console=True)

# first get a GeoDataFrame of neighborhood geometries
places = ['Hyde Park, London, UK',
          'Kensington Gardens, London, UK',
          'Regents Park, London, UK',
          'Hampstead Heath, London, UK',
          'Alexandra Park, London, UK',
          'Clissold Park, London, UK',
          'Finsbury Park, N4 2NQ, London, UK',
          'Russell Square, London, UK']
gdf = ox.geocode_to_gdf(places)

# OPTION 1: display all neighborhoods in a single ax
ax = gdf.plot()
ax.axis('off')

# OPTION 2: display each neighborhood in its own ax in a single fig
fig, axes = plt.subplots(nrows=2, ncols=4)
for i, ax in zip(gdf.index, axes.flat):
    gdf.loc[i:i].plot(ax=ax)
    ax.axis('off')
plt.show()

请注意，从 OSMnx v0.15.0 开始，gdf_from_place 和 gdf_from_places 函数已被弃用并被 geocode_to_gdf 函数取代。有关详细信息，请参阅 the docs。

Osmnx：如何使 plot_shape() 在 pyplot 子图中工作？

Osmnx: how to make plot_shape() work in pyplot subplots?

python

matplotlib

shapefile

subplot

osmnx