根据python中的另一个列表匹配列表的元素，其中一个列表的元素是另一个列表的子字符串

Question

listA = ['abcd754_efgh_20160110_165623.frf', 'abcd754_efghijk_20160110_162419.frf', 'abcd755_mno_20160110_165287.frf', 'abcd755_mnopqr_20160110_164562.frf'  ]
listB = ['abcd754_efgh', 'abcd754_efghijk_', 'abcd755_mno_', 'abcd755_mnopqr_']

I have list A and list B. List A may sometimes have one or 2 elements missing. Based on that I need to create list C with elements in list B by maintaining the same order.

I have been unable to find a solution.

Answer 1

You could do something like this:

listA = ['abcd754_efgh_20160110_165623.frf', 'abcd754_efghijk_20160110_162419.frf', 'abcd755_mno_20160110_165287.frf']
listB = ['abcd754_efgh', 'abcd754_efghijk_', 'abcd755_mno_', 'abcd755_mnopqr_']
listC = []

for b in listB:
    if any(a.startswith(b) for a in listA):
        listC.append(b)

print listC

outputs ['abcd754_efgh', 'abcd754_efghijk_', 'abcd755_mno_']

You didn't specify if you want elements in listB that are or aren't in listA, so add a not before any if you want the other way.

This is a simple quadratic solution, if you have a lot of elements you'll need something more efficient

Answer 2

Using a listcomp you can say:

listC = [b for b in listB if any(b in a for a in listA)]

For

listA = ['abcd754_efgh_20160110_165623.frf', 'abcd754_efghijk_20160110_162419.frf', 'abcd755_mno_20160110_165287.frf']
listB = ['abcd754_efgh', 'abcd754_efghijk_', 'abcd755_mno_', 'abcd755_mnopqr_']

This prints

['abcd754_efgh', 'abcd754_efghijk_', 'abcd755_mno_']