How to each item in list with all values of another list in Python

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All combinations of a list of lists

I've been trying to use python to add two lists of strings together and I can't get it work with the different arrangements of for loops that I've tried. What I have is two lists and I want to make a third list from the other two, so that index[0] from list 1 has all of the indexes from list 2 added to it in turn (each being a separate entry in the new list), and then the same for index[1] from list1, and so on..

snippets1 = ["aka", "btb", "wktl"]
snippets2 = ["tltd", "rth", "pef"]

resultlist = ["akatltd", "akarth", "akapef", "btbtltd", "btbrth", "btbpef", "wktltltd", "wktlrth", "wktlpef"]

I know the answer is simple but no matter what I do I keep get something that doesn't work at all, or it adds snippets1[0] to snippets2[0], snippets1[1] to snippets2[1] and so on. Help please!

score 11 · Answer 1 · answered Nov 02 '12 at 17:22

11

import itertools

snippets1 = ["aka", "btb", "wktl"]
snippets2 = ["tltd", "rth", "pef"]

resultlist = [''.join(pair) for pair in itertools.product(snippets1, snippets2)]

answered Nov 02 '12 at 17:22

Oleh Prypin

31,366
9
86
97

score 3 · Accepted Answer · answered Nov 02 '12 at 17:26

3

You can try like this

resultlist=[]
for i in snipppets1:
 for j in snippets2:
  resultlist.append(i+j)
print resultlist

answered Nov 02 '12 at 17:26

Vinil Narang

653
6
11

1

Thanks. This is what I was trying to get to initially but I kept messing it up – spikey273 Nov 02 '12 at 17:34

score 3 · Answer 3 · answered Nov 02 '12 at 17:42

And for completeness sake, I suppose I should point out the one liner not using itertools (but the itertools approach with product should be preferred):

[i+j for i in snippets1 for j in snippets2]
# ['akatltd', 'akarth', 'akapef', 'btbtltd', 'btbrth', 'btbpef', 'wktltltd', 'wktlrth', 'wktlpef']

How to each item in list with all values of another list in Python

3 Answers3