>>> arr = ndtest(3)
>>> arr.reindex({'a': 'a1,a2,a3'})
[...]
KeyError: "axis 'a' not found in {{0}}"
>>> arr.reindex('a', 'a1,a2,a3')
a a1 a2 a3
1.0 2.0 nan
>>> arr.reindex({'a': 'a=a1,a2,a3'})
a a1 a2 a3
1.0 2.0 nan
>>> arr.reindex({'a': Axis('a=a1,a2,a3')})
a a1 a2 a3
1.0 2.0 nan
vs stumbled on this one