Function Definition: Matching two input lists

Question

def match_numbers (nlist, nlist1):
    '''Returns the integer string whose first three numbers are on the first list'''
    for x in nlist:
    for x in nlist1:
        print(x)

So suppose the first list was ['543', '432'] and the second list had ['543242', '43299919', '2322242', '245533'], and I need the function to match 543 and 432 with its longer version on the second list, how can I get my code to do this?

sam · Answer 1 · 2015-10-17T01:48:30.440

0

Try this:

[x for x in a for i in b if i == x[:len(i)]]

Output:

['543242', '43299919']

edited Oct 17 '15 at 01:48

answered Oct 17 '15 at 01:39

sam

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score 0 · Accepted Answer · answered Oct 17 '15 at 01:45

If you have a large list, this will perform slightly better

list1 = ['543', '432']
list2 = ['543242', '43299919', '2322242', '245533']

def match_numbers (nlist, nlist1):
    results = {}
    for x in nlist1:
        results.setdefault(x[0:3], [])
        results[x[0:3]].append(x)

    for x in nlist:
        if x in results:
            print results[x]


match_numbers(list1, list2)

Function Definition: Matching two input lists

2 Answers2