ENH: Add iter_regex and find_features

Fixes #612. Adds iter_regex to skbio._sequence.BiologicalSequence and
find_features to skbio._sequence.NucleotideSequence. Supported features are
currently purine_run and pyrimidine run, but more can be added by specifying
additional regular expressions.
No, because which features you might be looking for are different for RNA
vs. DNA vs. Protein sequences


On Tue, Aug 12, 2014 at 3:46 PM, Daniel McDonald <notifications@github.com>
wrote:

> In skbio/sequence/_sequence.py:
>
> > @@ -1324,6 +1350,34 @@ def reverse_complement(self):
> >          return self._complement(reversed(self))
> >      rc = reverse_complement
> >
> > +    def find_features(self, feature_type, min_length=1):
> > +        """Search the sequence for features
> > +
> > +        Parameters
> > +        ----------
> > +        feature_type : {'purine_run', 'pyrimidine_run'}
>
> Doesn't that suggest find_features should be defined in the base?
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/biocore/scikit-bio/pull/613/files#r16137574>.
>