环形图地图

Linda.W

王老师，请教如何在地图上绘制站点环形图占比图的函数和方法。nested pie函数中没有设置x,y经纬度参数。

MeteoInfo

可以先创建一个地图坐标系，绘制相关地图数据。利用地图坐标系的 data2pixel 函数讲站点经纬度转换为图形像素坐标，然后以该坐标为中心创建一个坐标系，在其中绘制环形饼图即可。参考下面的代码：

1. #Creat a map axes
   
2. ax = axesm()
   
3. geoshow('china', edgecolor='b')
   
4. grid()
   
5. 
   
6. #Draw figure so we can use data2pixel function
   
7. draw()
   
8. x, y = ax.data2pixel(90, 30)
   
9. print x, y
   
10. 
    
11. #Draw a fixed pixels size pie chart at a specific longitude/latitude
    
12. s = 80
    
13. x -= s * 0.5
    
14. y -= s * 0.5
    
15. ax1 = axes(position=[x, y, s, s], units='pixels')
    
16. x = [1, 3, 0.5, 2.5, 2]
    
17. size = 0.3
    
18. patchs, = pie(x, startangle=90,
    
19.     wedgeprops=dict(edgecolor='w', linewidth=2, width=size))
    
20. pie(x, startangle=90, radius=1-size, cmap='GMT_seis',
    
21.     wedgeprops=dict(edgecolor='w', linewidth=2, width=size))

#Creat a map axes<br /> ax = axesm()<br /> geoshow('china', edgecolor='b')<br /> grid()<br /> <br /> #Draw figure so we can use data2pixel function<br /> draw()<br /> x, y = ax.data2pixel(90, 30)<br /> print x, y<br /> <br /> #Draw a fixed pixels size pie chart at a specific longitude/latitude<br /> s = 80<br /> x -= s * 0.5<br /> y -= s * 0.5<br /> ax1 = axes(position=[x, y, s, s], units='pixels')<br /> x = [1, 3, 0.5, 2.5, 2]<br /> size = 0.3<br /> patchs, = pie(x, startangle=90,<br />     wedgeprops=dict(edgecolor='w', linewidth=2, width=size))<br /> pie(x, startangle=90, radius=1-size, cmap='GMT_seis',<br />     wedgeprops=dict(edgecolor='w', linewidth=2, width=size))