/usr/lib64/python2.4/site-packages/numpy/core/ma.py:604: UserWarning: Cannot automatically convert masked array to numeric because data
is masked in one or more locations.
warnings.warn("Cannot automatically convert masked array to "\
Traceback (most recent call last):
File "./generate-worldmap.py", line 205, in ?
sys.exit(main())
File "./generate-worldmap.py", line 200, in main
draw_client_density(r)
File "./generate-worldmap.py", line 50, in draw_client_density
colorbar(cax=cax,format=JefFormatter()) # draw colorbar
File "/usr/lib64/python2.4/site-packages/matplotlib/pylab.py", line 324, in colorbar
ret = gcf().colorbar(mappable, cax = cax, **kw)
File "/usr/lib64/python2.4/site-packages/matplotlib/figure.py", line 766, in colorbar
cb = cbar.Colorbar(cax, mappable, **kw)
File "/usr/lib64/python2.4/site-packages/matplotlib/colorbar.py", line 501, in __init__
ColorbarBase.__init__(self, ax, **kw)
File "/usr/lib64/python2.4/site-packages/matplotlib/colorbar.py", line 161, in __init__
self.draw_all()
File "/usr/lib64/python2.4/site-packages/matplotlib/colorbar.py", line 172, in draw_all
self._config_axes(X, Y)
File "/usr/lib64/python2.4/site-packages/matplotlib/colorbar.py", line 196, in _config_axes
ticks, ticklabels, offset_string = self._ticker()
File "/usr/lib64/python2.4/site-packages/matplotlib/colorbar.py", line 314, in _ticker
b, ticks = self._locate(b)
File "/usr/lib64/python2.4/site-packages/matplotlib/colorbar.py", line 454, in _locate
b = self.norm(self._boundaries, clip=False).filled()
File "/usr/lib64/python2.4/site-packages/matplotlib/colors.py", line 658, in __call__
raise ValueError("minvalue must be less than or equal to maxvalue")
ValueError: minvalue must be less than or equal to maxvalue