Select rows by partial string match in index

Question

Having a series like this:

ds = Series({'wikipedia':10,'wikimedia':22,'wikitravel':33,'google':40})

google        40
wikimedia     22
wikipedia     10
wikitravel    33
dtype: int64

I would like to select the rows where 'wiki' is a part of the index label (a partial string label).

For the moment I tried

ds[ds.index.map(lambda x: 'wiki' in x)]

wikimedia     22
wikipedia     10
wikitravel    33
Name: site, dtype: int64

and it does the job, but somehow the index cries for 'contains' just like what the columns have...

Any better way to do that?

Answer 1

A somewhat cheeky way could be to use loc:

In [11]: ds.loc['wiki': 'wikj']
Out[11]:
wikimedia     22
wikipedia     10
wikitravel    33
dtype: int64

This is essentially equivalent to ds[ds.index.map(lambda s: s.startswith('wiki'))].

To do contains, as @DSM suggests, it's probably nicer to write as:

ds[['wiki' in s for s in ds.index]]

Answer 2

Another solution using filter, see here:

>>> ds.filter(like='wiki', axis=0)
wikimedia     22
wikipedia     10
wikitravel    33
dtype: int64