On Jul 28, 9:46 pm, Andrew Savige <[EMAIL PROTECTED]> wrote: > Python beginner here. > > For a string 'ABBBCC', I want to produce a list ['A', 'BBB', 'CC']. > That is, break the string into pieces based on change of character. > What's the best way to do this in Python? > > Using Python 2.5.1, I tried: > > import re > s = re.split(r'(?<=(.))(?!\1)', 'ABBBCC') > for e in s: print e > > but was surprised when it printed: > > ABBBCC > > I expected something like: > > A > A > BBB > B > CC > C > > (the extra fields because of the capturing parens).
Using itertools: import itertools s = 'ABBBCC' print [''.join(grp) for key, grp in itertools.groupby(s)] Using re: import re pat = re.compile(r'((\w)\2*)') print [t[0] for t in re.findall(pat, s)] By the way, your pattern seems to work in perl: $ perl -le '$, = " "; print split(/(?<=(.))(?!\1)/, "ABBBCC");' A A BBB B CC C Was that the type of regular expressions you were expecting? -- Hope this helps, Steven -- http://mail.python.org/mailman/listinfo/python-list
