[Matplotlib-users] Basemap drawparallels failed issue

[Dave X. <xi...@gm...>]

Hi,

I am a new user of matplotlib Basemap. I tried to draw  the latitude with
interval 0.1 degree using drawparallels, but failed.  I wonder if the
drawparallels can draw latitude lines with small interval instead of
integer values. (drawmeridian can work with small interval 0.1).

Does anyone have any idea to fix this issue?

Thanks!

Dave

#here is a test program to test the drawparallels function
#testbasemap.py
from mpl_toolkits.basemap import Basemap
import matplotlib.pyplot as plt
import numpy as np
import math

latmin=36.803200
latmax=37.306640
lonmin=-76.396026
lonmax=-75.602331

latmin1=math.floor(latmin)
latmax1=math.ceil(latmax)
lonmin1=math.floor(lonmin)
lonmax1=math.ceil(lonmax)

m=Basemap(projection='merc',resolution='h',llcrnrlat=latmin,urcrnrlat=latmax,llcrnrlon=lonmin,urcrnrlon=lonmax)
m.drawcoastlines()
m.drawmapboundary(fill_color='aqua')
m.fillcontinents(color='coral',lake_color='aqua')
meridians = np.arange(lonmin1,lonmax1,0.1)
m.drawmeridians(meridians,labels=[1,1,0,1],fmt='%5.2f')
parallels=np.arange(latmin,latmax,0.1)
m.drawparallels(parallels,labels=[1,1,0,1],fmt='%5.2f')
plt.savefig('test.png')


#####################################################################
The error message is as follows:

Traceback (most recent call last):
  File "testbasemap.py", line 25, in <module>
    m.drawparallels(parallels,labels=[1,1,0,1],fmt='%5.2f')
  File
"/usr/local/lib/python2.7/site-packages/mpl_toolkits/basemap/__init__.py",
line 2067, in drawparallels
    if t is not None: linecolls[int(lat)][1].append(t)
KeyError: 36