for loop/list-comprehensions to apply zip_longest for list of lists combinations to get (l1[0]:l2[0]-CodePudding

I have been working on combining lists of lists...testing answers to various questions on zip, zip_longest, lists, list comprehensions, iteration through lists of unequal lengths lists of lists, but I have been unable to find one that fixes my issue. I am now defeated.

This may very well be a result of my inexperience, but I've run out of places to look.

I have two lists of lists with the internal lists having various lengths.

I want to zip_longest each internal list with the following type of result: [('1', '1. A method'), ('2', '2. The method'), ('Description', '3.Description'), etc.]

The attempts shown below get me results I like but the code generats cross combining of list_1[0] with list_2[1]. I want only combining of lists at the same index (list_1[0] with list_2[0]) then 1:1, 2:2.

from itertools import zip_longest
claim_text = [['1. A method', '2. The method', '3. Description'],
              ['1. A method', '2. The method', '3. The method', '5. The method']]; 
claim_num =  [['1', '2'], ['1', '2', '3']]

combined = []
for i in claim_text:    
   for x in claim_num:
       combined.append(list(itertools.zip_longest(x,i, fillvalue='Description')))
print(combined)

another approach:

[(list(itertools.zip_longest(a,b, fillvalue='Description'))) for a in claim_num for b in claim_text]

Any help is appreciated.

CodePudding user response：

Do you want to zip_longest the first num with the first text, second null with second text, etc.?

Then start by combining the sublists of the two inputs with zip:

[list(zip_longest(a, b, fillvalue='Description'))
 for a, b in zip(claim_num, claim_text)]

Output:

[[('1', '1. A method'),
  ('2', '2. The method'),
  ('Description', '3. Description')],
 [('1', '1. A method'),
  ('2', '2. The method'),
  ('3', '3. The method'),
  ('Description', '5. The method')]]