Python: how to copy between lists using lists, e.g. list1[index1] = list2[index2]

Question

Say we have two lists of values, list1 and list2 , and tow lists of indices, index1 and index2 . How do we copy elements with position index2 in list2 to elements with position index1 in list1 . In Matlab, for example, we can simply write list1[index1] = list2[index2] , but strangely this does not seem to work in Python. Also, how do we do this if index1 and/or index2 is a list of booleans?

For example, say list1 = ['a','b','c','d','e'] and list2 = ['A','B','C','D','E'] and index1 = [0,1,3] and index2 = [1,2,4] with the result of list1[index1] = list2[index2] being list1: ['B','C','c','E','e'] .

In the case of boolean, the same output should be achived with index1 = [True,True,False,True,False] and index2 = [False,True,True,False,True] .

PS: It is clear how to do this with a for loop. I am looking for a more "pythonic" way, eg list comprehension. Thank you

PPS: After some experimentation, I defined a class MyList which inhereted from class Python's list and modified __getitem__ and __setitem__ to accept lists of integers or booleans. The class definition is given in my post here How to extend list class to accept lists for indecies in Python, eg to use list1[list2] = list3[list4]

Answer 1

You can use a simple for-loop with enumerate :

list1 = ['a','b','c','d','e']
list2 = ['A','B','C','D','E']
index1 = [0,1,3]
index2 = [1,2,4]

for i, val in enumerate(index1):
    list1[val] = list2[index2[i]]

print(list1)

Output:

 ['B', 'C', 'c', 'E', 'e']

Or alternatively with zip :

list1 = ['a','b','c','d','e']
list2 = ['A','B','C','D','E']
index1 = [0,1,3]
index2 = [1,2,4]

for a, b in zip(index1, index2):
    list1[a] = list2[b]

print(list1)

Output:

 ['B', 'C', 'c', 'E', 'e']

As far as I can see, the boolean case is a completely different one, and should be asked in a separate question.

Answer 2

Use zip and combine the elements of the two index lists.

list1 = ['a', 'b', 'c', 'd', 'e']
list2 = ['A', 'B', 'C', 'D', 'E']
index1 = [0, 1, 3]
index2 = [1, 2, 4]

for i1, i2 in zip(index_1, index_2):
    list1[i1] = list2[i2]

print(list1)

Answer 3

list1 = ['a','b','c','d','e']
list2 = ['A','B','C','D','E']
index1 = [0,1,3]
index2 = [1,2,4]
x=0
for i in index1:
    list1[i] = list2[index2[x]]
    x+=1
print(list1)