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pythonlistcomparison

Case-insensitive comparison of two lists

I have 2 lists. The first is list_A = ['Sasi', 'Babu', 'kuttapppan', 'mathayi'] and my second list is list_B = ['Raman', 'Kesavan', 'sasi', 'unni', 'Kuttappan'].

I want to compare these two lists and identify the values which are duplicated in the second list regardless of if it starts with a capital letter or a lowercase letter. I've tried the following method:

if not [name for name in list_A if name in list_B]:
     print name

But it is not working as expected.

Solution 
  • #Might be better if we are dealing with huge lists.  

list_A = ['Sasi', 'Babu', 'kuttapppan', 'mathayi']
list_B = ['Raman', 'Kesavan', 'sasi', 'unni', 'Kuttappan'].

d = [x.lower() for x in list_A] # make dict of list with less elements  
for m in list_B:  # search against bigger list  
    if m.lower() in d: print(m)