Python Extended List Slicing
.I never knew about this optional third parameter to list slices—in addition to e.g. getting the third to fifth items in a list with somelist[2:5], you can also get every nth item with somelist[::n].
This makes it very easy to get every odd or even item in a list, odd with somelist[::2] and even with somelist[1::2].
Where I think this is particularly handy is if you have to grab e.g. three-line chunks out of some text:
chunks = []
lines = text.split("\n")
for i in range(0, len(lines))[::3]:
chunk = []
chunk.append(lines[i])
chunk.append(lines[i+1])
chunk.append(lines[i+2])
chunks.append("\n".join(chunk))
The docs on extended slices are here.
02 Oct 2009 at 00:31
When i clicked on the headline i thought i was going to see some pythons sliced into pieces! How stupid! LOL.