On Monday, January 9, 2017 at 2:22:19 PM UTC, Tim Chase wrote: > On 2017-01-08 22:58, Deborah Swanson wrote: > > 1) I have a section that loops through the sorted data, compares two > > adjacent rows at a time, and marks one of them for deletion if the > > rows are identical. > > > > I'm using > > > > for i in range(len(records)-1): > > r1 = records[i] > > r2 = records[i+1] > > if r1.xx = r2.xx: > > . > > . > > and my question is whether there's a way to work with two adjacent > > rows without using subscripts? > > I usually wrap the iterable in something like > > def pairwise(it): > prev = next(it) > for thing in it: > yield prev, thing > prev = thing > > for prev, cur in pairwise(records): > compare(prev, cur) > > which I find makes it more readable. > > -tkc
Or from https://docs.python.org/3/library/itertools.html#itertools-recipes:- def pairwise(iterable): "s -> (s0,s1), (s1,s2), (s2, s3), ..." a, b = tee(iterable) next(b, None) return zip(a, b) This and many other recipes are available in the more-itertools module which is on pypi. -- https://mail.python.org/mailman/listinfo/python-list
