Question

我使用以下代码段绘制了底图：

#setting the size
plt.figure(figsize=(20,10))
#iterating through each country in shape file and filling them with color assigned using the colors array
for nshape,seg in enumerate(m.countries):
#getting x,y co-ordinates
     xx,yy = zip(*seg)
#getting the corresponding color
     color = colors[countryisos[nshape]]
#plotting them on the map
     plt.fill(xx,yy,color,edgecolor=color)
#setting the parallels with 10 degree interval from -90 to 90 degrees  
parallels = np.arange(-80.,81,10.)
m.drawparallels(parallels,labels=[True,True,True,True])
#setting the meridians with 20 degree interval from -180 to 180 degrees
meridians = np.arange(10.,351.,20.)
m.drawmeridians(meridians,labels=[True,False,False,True])
#setting the title for the plot
plt.title('Number of Disasters by Country: 1981-2014')

使用此功能将三种颜色分配给颜色数组。

colors={}
#iterating through each country in shape file and setting the corresponding color
for s in countryisos:
    if countvalues[s]<=200:
      colors[s] = 'orange'
    elif countvalues[s]>200 and countvalues[s]<=400:
      colors[s] = 'yellow'
    else:
      colors[s] = 'red'

如何设置此图表的图例，显示三种颜色，每种颜色定义一个范围？我不能使用＆＃39;标签＆＃39; plot函数内部的参数，因为它在for循环中。

Answer 1

使用matplotlib中的补丁解决了这个问题。我刚刚在下面添加了此代码以显示自定义图例。

#setting the legend for the plot using patch
lt = mpatches.Patch(color='orange', label='<200')
btwn = mpatches.Patch(color='yellow', label='200-400')
gt = mpatches.Patch(color='red', label='>400')
plt.legend(handles=[lt,btwn,gt],title='Number of disasters', loc=3)

在Matplotlib底图中显示图例

1 个答案: