使用Python Basemap和Pyproj时出现运行时错误？

Question

我用Spyder这个开发环境写了一个脚本，利用mpl_toolkits的basemap库来绘制GPS轨迹，箭头表示方向，颜色根据速度来区分。一切运行得很好，直到我把pandas升级到了0.13版本。

我的数据大概是这样的：

                            lon        lat     bearing  speed m/s
2014-01-20 16:26:00 -170.681264 -14.290060         NaN        NaN
2014-01-20 16:27:00 -170.681259 -14.290074  163.753636   0.026727
2014-01-20 16:28:00 -170.681259 -14.290074  180.000000   0.001172
2014-01-20 16:29:00 -170.681259 -14.290077  180.000000   0.004981

ll = [-14.294238,-170.683732] 
ur = [-14.286362, -170.673260]
gMap = Basemap(projection='merc', resolution='f',
           llcrnrlon=ll[1], llcrnrlat=ll[0],
           urcrnrlon=ur[1], urcrnrlat=ur[0],ax=ax)

现在当我尝试运行这一行代码：

gMap.quiver(AllPoints['lon'],AllPoints['lat'],sin(radians(AllPoints['bearing'])),cos(radians(AllPoints['bearing'])),latlon=True,color=Points['speed m/s'].values,scale=40,cmap=plt.cm.rainbow)

我遇到了这个错误：

Traceback (most recent call last):
  File "", line 1, in 
  File "C:\Python27\lib\site-packages\mpl_toolkits\basemap\__init__.py", line 559, in with_transform
    x, y = self(x,y)
  File "C:\Python27\lib\site-packages\mpl_toolkits\basemap\__init__.py", line 1148, in __call__
    xout,yout = self.projtran(x,y,inverse=inverse)
  File "C:\Python27\lib\site-packages\mpl_toolkits\basemap\proj.py", line 286, in __call__
    outx,outy = self._proj4(x, y, inverse=inverse)
  File "C:\Python27\lib\site-packages\mpl_toolkits\basemap\pyproj.py", line 388, in __call__
    _proj.Proj._fwd(self, inx, iny, radians=radians, errcheck=errcheck)
  File "_proj.pyx", line 124, in _proj.Proj._fwd (src/_proj.c:1594)
RuntimeError

如果我去掉latlon=True这个参数，代码就能运行，但数据就不显示了。有没有人知道问题出在哪里？

Answer 1

不知道什么原因，Basemap.quiver在升级后不太喜欢直接用Pandas的DataFrame列。 我把代码从：gMap.quiver(AllPoints['lon'], AllPoints['lat']....) 改成了：gMap.quiver(AllPoints['lon'].values, AllPoints['lat'].values....) 现在一切都正常了。