CODEWITHSUNDEEP
pythonpandaslist
adikh
adikh

Reputation: 306

Matching a pattern from list of lists

I am working with a list of lists and I want to match patterns in lists. For instance, I have shown a list of lists below. 

 x = [[['a', 5],
      ['b', 0.11],
      ['c', 0.85]]
     [['a', 'b', 0.5],
      ['b', 'c', 1.0],
      ['c', 'a', 0.7]],
     [['a', 'b', 'c', 0.9],
      ['b', 'c', 'a', 0.4],
      ['a', 'c', 'b', 1.0]]]

Now I want to give an input like ("a","b","c") then it should give me respective value ex. 0.9 in above list.

I tried to use

 if ["a","b","c"] in x : 
>>> False.

But it is not working that way. How can I solve this ? Please suggest any solution.

Aditya.

Upvotes: 0

Views: 1017

Answers (5)

DarrylG
DarrylG

Reputation: 17156

Recursively searches regardless of levels of sublists

Since poster requires:

this list is dynamic and it can have more than 3 lists inside

def find(lst, t, result = None):
  if not isinstance(t, list): # insure t is a list
    t = [t]

  if result is None:  # Set default result
    result = []

  for sublist in lst: # outer list loop
    if isinstance(sublist, list):
      if sublist[:-1] == t:
        result.append(sublist[-1])
        return result
      else:
        find(sublist, t, result) # recursively check sublists

  return result

x = [[['a', 5],
      ['b', 0.11],
      ['c', 0.85]],
     [['a', 'b', 0.5],
      ['b', 'c', 1.0],
      ['c', 'a', 0.7]],
     [['a', 'b', 'c', 0.9],
      ['b', 'c', 'a', 0.4],
      ['a', 'c', 'b', 1.0]],
    [[
      ['a', 'a', 'c', 2],    # additional level added
      ['x', 'a', 5]]]]

print(find(x, 'a'))              # [5]
print(find(x, ['a', 'b']))       # [0.5]
print(find(x, ['a', 'b', 'c']))  # [0.9]
print(find(x, ['a', 'a', 'c']))  # [2]

Upvotes: 0

user9772352
user9772352

Reputation:

Try this code

x = [
     [['a', 5],['b', 0.11],['c', 0.85]],
     [['a', 'b', 0.5],['b', 'c', 1.0],['c', 'a', 0.7]],
     [['a', 'b', 'c', 0.9],['b', 'c', 'a', 0.4],['a', 'c', 'b', 1.0]]]

checklist = ['a', 'b', 'c']

return_value = [j[-1]   for i in x for j in i if j[:-1] == checklist][0]
print(return_value)

>> 0.9

with this code, you can find any pattern that exists by changing checklist like checklist = ['a'] output will be 5

Upvotes: 2

boot-scootin
boot-scootin

Reputation: 12515

x = [
        [
            ['a', 5],
            ['b', 0.11],
            ['c', 0.85]
        ],
        [
            ['a', 'b', 0.5],
            ['b', 'c', 1.0],
            ['c', 'a', 0.7]
        ],
        [
            ['a', 'b', 'c', 0.9],
            ['b', 'c', 'a', 0.4],
            ['a', 'c', 'b', 1.0]
        ]
]

# Define search term as string
search = 'abc'
desired_value = None
for collection in x:
    for row in collection:
        # convert everything but the last element in each row to a string for easy comparison
        key = ''.join(row[:-1])
        # if you've found a key matching your search criterion, grab the last value for that row
        if search == key:
            desired_value = row[-1]
            break

Upvotes: 0

azro
azro

Reputation: 54148

The first thought would be to check that all elements of the input are in the subsublist, like this

value = ['a', 'b', 'c']
for sublist in x:
    for part in sublist:
        if all(v in part for v in value):
            print(part)

Or setting the value as a set you can check issubset

value = {'a', 'b', 'c'}
for sublist in x:
    for part in sublist:
        if value.issubset(set(part)):
            print(part)

But it doesn't look at the order, as all are string you could simply concat the elements in part and check if abc is in

value = 'abc'
for sublist in x:
    for part in sublist:
        if value in ''.join(map(str, part)):
            print(part)

Upvotes: 0

Quang Hoang
Quang Hoang

Reputation: 150735

Lists are not hashable, you need to use tuple:

xx = {tuple(a[:-1]):a[-1]  for b in x for a in b}

if ('a','b','c') in xx: print(xx[('a','b','c')])
# 0.9

Upvotes: 2

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