Python list basics

Question

I was going through the Apriori algorithm and was trying to solve it by using user defined function. The code is available on Github -: https://gist.github.com/marcelcaraciolo/1423287

I am not able to get these two lines and how they are iterating in loops.

            L1 = list(freq_sets[i])[:k - 2]
            L2 = list(freq_sets[j])[:k - 2]

Actual function containing these line :

def aprioriGen(freq_sets, k):
    "Generate the joint transactions from candidate sets"
    retList = []
    lenLk = len(freq_sets)
    for i in range(lenLk):
        for j in range(i + 1, lenLk):
            L1 = list(freq_sets[i])[:k - 2]
            L2 = list(freq_sets[j])[:k - 2]
            L1.sort()
            L2.sort()
            if L1 == L2:
                retList.append(freq_sets[i] | freq_sets[j])
    return retList

question from:https://stackoverflow.com/questions/66057951/python-list-basics

Answer 1

Waitting for answers