Deleting indices from dictionary

Question

Given is a list with unsorted indices in a list of length n. Each element of the list is only once contained. So the list looks like this

L = [13, 145, 70001, 34, ..., 533]

Also given is a dictionary d which numerical values as key. All values are element {0,1}. Like

d = {
        "[some data]" : 0,
        "[some data]" : 1,
        "[some data]" : 1,
        "[some data]" : 1,
        ...
        "[some data]" : 0
    }

There are a lot more entries in the dictionary d then in the list L.

What I want to do is deleting data from the dictionary for each position (index) from L if it is a 0.

The problem that I see while proceeding it that after the each deletion the indices need to be shifted since the position within dictionary is changing. Which is quiet inefficient regarding on a large number of items in L. There must be an efficient way of proceeding this task.

Any ideas and suggestions are highly appreciated!

Answer 1

Note that you should not expect to be able to do this as most dictionary implementations are not ordered, but Python's is since 3.6 and a part of the spec in 3.7 - but onto the question.

We can use a dictionary comprehension with enumerate to make a new dictionary so we do not have to worry about the index shifting business that worries you.

L_ = set(L)
d = {k: v for i, (k, v) in enumerate(dict.items()) if i not in L_ and v}