Wrong list being returned in python

Question

def mainCall(nodeGroup):

    maxScore = -9999999
    maxPart = []
    tempPartition = []
    tempScore = 0.0

    for j in range(2, 1+nodes/2):

        nodeGroup = cho         


        

Answer 1

When you say

maxPart = tempPartition

you are not creating a copy of tempPartition but you are making the maxPart also to point to the same list that tempPartition points to. To really make a copy, you can use slicing notation like this

maxPart[:] = tempPartition

or

maxPart = tempPartition[:]

The difference between maxPart[:] = tempPartition and maxPart = tempPartition[:] is that the former mutates the maxPart and copies all the values from tempPartition to maxPart and latter creates a new list with a copy of all the data in tempPartition and makes the maxPart points to the newly created list.