I  found an errorbar with transform option does not work properly.
When you use transform option, only X-Y trace shifts, but not errorbar.
See my sample program below.
The matlotlib version is 0.90.1, though it seems the latest 0.91.1 ends up same.  
 
I want to plot some overlay traces with errorbar.
Can anybody help me?
 
Noriko Minakawa
 
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import pylab as P
from matplotlib.transforms import offset_copy
 
x =  [0.1, 1,   5,    6,   9,   11,  12,  13,  14,    15,  16, 21,  22,  23,  24,  40]
y =  [0.1,0.1, 0.1, 1.5, 0.2, 1.2, 100,  250,  180, 90, 0.1, 0.1 ,1.2, 13.5,0.1, 0.1]
er = [1, 2, -1, 2, -5, 3, 6, -1, 3, 1, -2, 5, 2, -3, 2, 1]

fig = P.figure(figsize=(6,6))
ax = P.subplot(1,1,1)

transOffset = offset_copy(ax.transData, fig=fig, x = 0.2, y=0.2, units='inches')
ax.errorbar(x,y, yerr=er, transform=transOffset)
 
P.show()
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