[Matplotlib-users] basemap does not draw coastlines for certain choice of map boundaries

[Sourish B. <sou...@gm...>]

Hi all,

I discovered recently that basmap does not draw the coastline contours
properly for some choice of map boundaries. Specifically,

from mpl_toolkits.basemap import Basemap
map =
Basemap(projection='cyl',llcrnrlat=-22.,urcrnrlat=22.,llcrnrlon=78.,urcrnrlon=168.,resolution='l')
map.drawcoastlines()

results in the coastline of continental Asia not being drawn (see
attachment bad_contours.png). On the other hand, even subtly changing
the latitude boundaries, to

map =
Basemap(projection='cyl',llcrnrlat=-22.001,urcrnrlat=22.001,llcrnrlon=78.,urcrnrlon=168.,resolution='l')

results in all the coastlines being drawn (see attachment
good_contours.png). I presume this is a bug?

Here is my system info:

Operating system: Linux 3.2.0-41-generic #66-Ubuntu SMP Thu Apr 25
03:27:11 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

Matplotlib version: 1.1.0

Where I obtained matplotlib: SourceForge

Customizations to matplotlibrc: none

Thanks,

Sourish