底图 - 从 shapefile 添加文本

Basemap - adding text from shapefile

在阅读了关于注释和添加文本的 the basemap tutorial 之后,我仍然 运行 对此有一些疑问。

shapefile_info = m.readshapefile('/path/to/shapefile', 'shapefile_name')
for info, shape in zip(m.points_info, m.points):
    print info, shape

读取 shapefile 并打印出信息(使用上面的代码),我们得到以下输出:

{'LABELTYPE': 'ONE', 'LABELNAME': 'Start Point'} (2274311.7551607937, 759422.9640236866)

{'LABELTYPE': 'TWO', 'LABELNAME': 'End Point'} (1839892.6558604166, 947255.0800333266)

使用下面的代码...

from mpl_toolkits.basemap import Basemap
import matplotlib.pyplot as plt

l_one, l_two = 0, 0

m = Basemap(projection = 'merc', llcrnrlat= -2, urcrnrlat= 52, llcrnrlon= -137,\
            urcrnrlon= -58, lat_ts=40,resolution='i') 
m.shadedrelief()
m.drawcoastlines(linewidth=0.5)
m.drawcountries(linewidth=0.5)
m.drawstates(linewidth=0.5) 
m.drawparallels(np.arange(-90, 90, 10), linewidth = 0.2, 
                labels = [True, False, True, False], fontsize = 'x-small')
m.drawmeridians(np.arange(-180, 180, 10), linewidth = 0.2, 
                labels = [False, False, False, True], fontsize = 'x-small')

m.readshapefile('/path/to/shapefile', 'shapefile_name')
shapefile_info = m.readshapefile('/path/to/shapefile', 'shapefile_name')
for info, shape in zip(m.points_info, m.points):
    x, y = zip(shape)
    if info['LABELTYPE'] == 'ONE':
        m.plot(x, y, c = 'k', ms = 9., ls = "", mew = 1.,
                label = 'Start Point' if l_one == 0 else "_no-legend_")
        x, y = m(y[0], x[0])
        plt.plot(x, y, info['LABELNAME'])
        l_one += 1
    if info['LABELTYPE'] == 'TWO':
        m.plot(x, y, c = 'c', ms = 9., ls = "", mew = 1.,
                label = 'End Point' if l_two == 0 else "_no-legend_")
        x, y = m(y[0], x[0])
        plt.plot(x, y, info['LABELNAME'])
        l_two += 1

我收到以下错误: Illegal format string "Start Point"; two linestyle symbols

为什么我会收到此错误,我该如何修复它才能将字典中的文本放到绘图中?

要在 (x,y) 位置放置一些文本,您可以使用 plt.text() 而不是 plt.plot()(因为 plot 绘制的是线图,而不是文本)。

plt.text(x, y, text)

或者在这种情况下

plt.text(x, y, info['LABELNAME'])