Find differences between two matrix list-CodePudding

I found pretty much answers getting difference between 2 lists but couldn't able to find matrix lists.

I have 2 lists like below and I want to get the members which exist in "list1's first indice" and not exist in "list2's first indice"

I want to compare only the first indices of the list members and find the difference.

list1 = [(12, 'Text1'), (123, 'Text2'), (22, 'Text3')]
list2 = [('22', 'company1'), ('232', 'company2'), ('233', 'company3')]

(Not sure why list2's first indices has '' characters, couldn't able to remove it but I think still can be comparable.)

I'm using the code below but it takes hours(both indices has ~5000 members).

Is there any other way to calculate&find fastly?

notExist = []
for i,j in list1:
    for x,y in list2:
        if i == x:
            try:
                notExist.remove((i,j))
            except:
                print("Not Exist")
            break
        else:
            if i not in notExist:
                notExist.append((i,j))

CodePudding user response：

Convert them to dictionaries with key: (index, value) pairs:

list1 = [(12, 'Text1'), (123, 'Text2'), (22, 'Text3')]
list2 = [('22', 'company1'), ('232', 'company2'), ('233', 'company3')]

# convert these keys to strings, it'll make comparing a bit easier
d1 = {str(k): (idx, v) for idx, (k, v) in enumerate(list1)}

d2 = {k: (idx, v) for idx, (k, v) in enumerate(list2)}

# Now compare which dictionary has what
keys = ("12", "123", "22", "232")
results = []

for k in keys:
    # try to see if value is in the dictionary
    res = d1.get(k)

    # if it isn't, skip it
    if not res:
        continue
    
    # if it is, go ahead and test if it's in the other
    if d2.get(k):
        # skip if found
        continue
    
    # otherwise, append the key, index, and value
    results.append((k, *res))

CodePudding user response：

Convert both keys lists to sets and use - to find the difference:

>>> list1 = [(12, 'Text1'), (123, 'Text2'), (22, 'Text3')]
>>> list2 = [('22', 'company1'), ('232', 'company2'), ('233', 'company3')]

>>> s1 = set(x for x, _ in list1)
>>> s2 = set(int(x) for x, _ in list2)

>>> s1 - s2
{123, 12}
>>> s2 - s1
{232, 233}