matplotlib/matplotlib — pull request #630 by jenshnielsen (2011-12-16 08:51:04+00:00)
Title: Plot Colorbar in axes_grid1 with pcolormesh

This is identical to the standard colorbar and removes artifacts (white stripes)
in the pdf version of the ImageGrid plot.

The following example should illustrate the difference.

```python
from __future__ import division
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import ImageGrid,make_axes_locatable

F = plt.figure()
grid = ImageGrid(F, 111, # similar to subplot(111)
nrows_ncols = (2, 2),
axes_pad = 0.1,
add_all=True,
label_mode = "L",
share_all = True,
cbar_mode = "single",
)
data = np.arange(100).reshape(10,10)
for a in range(4):
ax = grid[a]
im = ax.imshow(data,interpolation='none',origin='lower')
v = grid.cbar_axes[0].colorbar(im)

plt.savefig('test_imagegrid.pdf')
```
Examples of the figures using current v1.1.x branch without and with the pcolormesh.

Before:
http://ubuntuone.com/5p9IYAFbFj9bbmN4A1dfo9
After:
http://ubuntuone.com/18vD21xtiQuVTFy96QVNOS