Joel Koltner wrote: > Is there an easy way to get a list comprehension to produce a flat list > of, say, [x,2*x] for each input argument? > > E.g., I'd like to do something like: > > [ [x,2*x] for x in range(4) ] > > ...and receive > > [ 0,0,1,2,2,4,3,6] > > ...but of course you really get a list of lists: > > [[0, 0], [1, 2], [2, 4], [3, 6]] > > I'm aware I can use any of the standard "flatten" bits of code to turn > this back into what I want, but I was hoping there's some way to avoid the > "lists of lists" generation in the first place?
>>> [x*y for x in range(4) for y in 1,2] [0, 0, 1, 2, 2, 4, 3, 6] > A slightly similar problem: If I want to "merge," say, list1=[1,2,3] with > list2=[4,5,6] to obtain [1,4,2,5,3,6], is there some clever way with "zip" > to do so? >>> items = [None] * 6 >>> items[::2] = 1,2,3 >>> items[1::2] = 4,5,6 >>> items [1, 4, 2, 5, 3, 6] Peter -- http://mail.python.org/mailman/listinfo/python-list
