Making a list from a list of lists, using the same repeated index number for each list created by the enumerate method

Question

My function desired_headers() removes tuples from "results" object which the first element in the tuple does NOT match any string in headers list. ['Fish', 'Dolphin'] from result1 object & ['Local Auth', 'bucket'] has been removed from result3.

Then it prints the index number and list of tuples as seen under current output below.

My aim is to "repack" the lists of tuples back together using my current output and store in an object.

headers2 = ['Group', 'Owner', 'Person in charge', 'Type of Service',
                    'Registered Care Categories*', 'Specialist Care Categories',
                    'Languages Spoken by Staff (other than English)','Single Rooms', 
                    'Shared Rooms','Facilities & Service']


result1 = [['Group', 'MacIntyre'], ['Person in charge', ' Vivienne Donald (Manager)'],
           ['Type of Service', 'good'], ['Fish', 'Dolphin'], ['Shared Rooms', '4']]

result2 = [['Group', 'Jameseson'], ['Type of Service', 'bad'], ['Shared Rooms', '8']]

result3 = [['Group', 'MacIntyre'], ['Person in charge', ' Vivienne Donald (Manager)'],
           ['Type of Service', 'good'], ['Shared Rooms', '4'], ['Local Auth', 'bucket']]

results = [result1, result2, result3]

#Removes tuples which the first element in the tuple does not matcch any string in headers2 list
def desired_headers():
  for index, z in enumerate(list(range(len(results)))):
     for i in list(range(len(results[z]))):
       if any(x in headers2 for x in results[z][i]):  
           print(index, results[z][i])



desired_headers()

Current Output:

0 ['Group', 'MacIntyre']
0 ['Person in charge', ' Vivienne Donald (Manager)']
0 ['Type of Service', 'good']
0 ['Shared Rooms', '4']
1 ['Group', 'Jameseson']
1 ['Type of Service', 'bad']
1 ['Shared Rooms', '8']
2 ['Group', 'MacIntyre']
2 ['Person in charge', ' Vivienne Donald (Manager)']
2 ['Type of Service', 'good']
2 ['Shared Rooms', '4']

Desired Output:

[[['Group', 'MacIntyre'],
  ['Person in charge', ' Vivienne Donald (Manager)'],
  ['Type of Service', 'good'],
  ['Shared Rooms', '4']],
 [['Group', 'Jameseson'], ['Type of Service', 'bad'], ['Shared Rooms', '8']],
 [['Group', 'MacIntyre'],
  ['Person in charge', ' Vivienne Donald (Manager)'],
  ['Type of Service', 'good'],
  ['Shared Rooms', '4']]]

Answer 1

You need something like this? This will group everything in a single list

# Removes tuples which the first element in the tuple does not matcch any string in headers2 list
def desired_headers():
    grouped_elements = []
    for index, z in enumerate(list(range(len(results)))):
        inner_loop = []
        for i in list(range(len(results[z]))):
            if any(x in headers2 for x in results[z][i]):
                inner_loop.append(results[z][i])

        grouped_elements.append(inner_loop)

    print(grouped_elements)

Answer 2

Try this

lv1 = [] # initialize an empty list which we will append to based on our criteria

for lst in results: # loop though each element of the list, which itself is a list
    lv2 = []
    for el in lst: # Same as above
        if el[0] in headers2: # check if first element of the list exists in headers2
            lv2.append(el)
    lv1.append(lv2)

lv1

Or if you want a function

def desired_headers(list_of_lists, inclution_list):
    lv1 = []

    for lst in list_of_lists:
        lv2 = []
        for el in lst:
            if el[0] in inclution_list:
                lv2.append(el)
        lv1.append(lv2)

    return lv1

desired_headers(list_of_lists=[result1, result2, result3], inclution_list=headers2)

Or if you are familiar with list comprehentions

result = [] 

for lst in [result1, result2, result3]:
    result.append([el for el in lst if el[0] in headers2])

result 

Answer 3

You could do it with a list comprehension:

filtered = [ [sl for sl in r if sl[0] in headers2] for r in results ]

output:

print(filtered)

[
    [
        ['Group', 'MacIntyre'],
        ['Person in charge', ' Vivienne Donald (Manager)'],
        ['Type of Service', 'good'],
        ['Shared Rooms', '4']
    ],
    [
        ['Group', 'Jameseson'],
        ['Type of Service', 'bad'],
        ['Shared Rooms', '8']
    ],
    [
        ['Group', 'MacIntyre'],
        ['Person in charge', ' Vivienne Donald (Manager)'],
        ['Type of Service', 'good'],
        ['Shared Rooms', '4']
    ]
]

If you have a lot of data, you may want to make a set out of headers2 to use in the list comprehension