How to define a variable in Python that points to or is a reference to a list member

[deanhystad]

I think you are asking the wrong question. Instead of asking "How can I do this thing I do in C for solving some problem?", skip the preamble and ask "How do I solve this problem?"

It's possible that Numpy arrays may work for your problem, but there is probably a better solution to the actual problem if you forget about trying to make Python work like C.

That said, you can always write a class.

class ArrayRef():
    def __init__(self, array, index=0, length=None):
        if length is None:
            length = len(array) - index
        self.length = length
        self.array = array
        self.index = index

    def __getitem__(self, index):
        if index >= self.length:
            raise IndexError
        return self.array[self.index + index]

    def __setitem__(self, index, value):
        if index >= self.length:
            raise IndexError
        self.array[self.index + index] = value

    def __iter__(self):
        return iter(self.array[self.index:self.index+self.length])

    def __repr__(self):
        return repr(self.array[self.index:self.index+self.length])

array = list(range(1, 21))
array_ref = ArrayRef(array, 5,  10)
array_ref[3] = 3.14
array[10] = -5
print(array)
print(array_ref)
print(sum(array_ref))

Output:
[1, 2, 3, 4, 5, 6, 7, 8, 3.14, 10, -5, 12, 13, 14, 15, 16, 17, 18, 19, 20]
[6, 7, 8, 3.14, 10, -5, 12, 13, 14, 15]
83.14

Still think you should reevaluate the problem you are trying to solve.