Check element in list of lists from items in another list of lists-CodePudding

I have one list of lists list1 and one list to check list2 that I'd like to run a for loop to check if elements from list2 are in list1, then append the element present to 'models' which is a list that pulls the first index from each list in list1.

No errors but I believe it might be because of the types I'm working with.

My scripts:

models = []
for item in cleaned_data:
    if item[0] not in models:
        models.append(item[0])

list1 = [['model1', 'yes', 'TT42'], 
        ['model2', 'yes', 'GG50'],
        ['model3', 'no', 'BB12']]

list2 = ['TT42', 'GG50', 'BB12']

...
models = ['model1', 'model2', 'model3']
...

for item in list1:
    if item == list2:
        models.append(item)
print(models)

OUTPUT> ['model1', model2', 'model3']

EXPECTED> [['model1', 'TT42'], ['model2', 'GG50'], ['model3', 'BB12']

CodePudding user response：

IIUC this will take your list 2 and compare it to your list 1 and find where all anything from list2 is equal to anything from list1 and add it to the models list

list1 = [['model1', 'yes', 'TT42'], 
        ['model2', 'yes', 'GG50'],
        ['model3', 'no', 'BB12']]

list2 = ['TT42', 'GG50', 'BB12']

single_list = [list1[x][y] for x in range(0, len(list1)) for y in range(0, len(list1[x]))]

models = [x for x in list2 for y in single_list if x ==y]
models

If this is not the expected results please provide more details and expected results.

CodePudding user response：

There are some issues with your code.

Your loop doesn't do anything, because when you do:

if item == list2:

The comparison will always be false, as the structure of item and list2 are different (e.g. you're comparing ["model1", "yes", "TT42"] with ['TT42', 'GG50', 'BB12']).

Your output is ['model1', model2', 'model3'] but it is because you defined it as such, the loop didn't change it.

Also, when you do:

models.append(item)

You were going to add a whole list inside the models variable. For instance, if the first comparison of the loop was correct, you'd have:

>>> print(models)
['model1', model2', 'model3', ['model1', 'yes', 'TT42']]

And it's obviously not what you want.

Here's a way of doing what you want:

list1 = [['model1', 'yes', 'TT42'], 
        ['model2', 'yes', 'GG50'],
        ['model3', 'no', 'BB12']]

list2 = ['TT42', 'GG50', 'BB12']
models = [[item[0], item[2]] for item in list1 if item[2] in list2]

Output:

>>> print(models)
[['model1', 'TT42'], ['model2', 'GG50'], ['model3', 'BB12']]