CF84 - 1 year ago 110
Python Question

# Python: how many times do the values in a list appear in a dictionary of lists?

Say you have a list of

`float`
values like this:

`l=[0.1,0.3,0.2]`

And a dictionary of lists like this:
`d1={0:[0.1,0.1,0.1,0.2], 1:[0.1,0.3,0.2], 2:[0.3,0.2,0.1]}`

What would be a Pythonic way of counting how many times each value in
`l`
appears in the sublists of
`d1`
?

The intended outcome would be a dictionary of lists like this:

`d2={0.1:[3,1,1], 0.2:[1,1,1], 0.3:[0,1,1]}`

where the key is the value in
`l`
and the sublist contains the number of occurrences of each value.

Can this be done using
`Counter`
? The order of the values in the sublists is not important.

NB: this question is not the same as this other, where a list of dictionaries is involved.

You can convert the values of `d1` to `Counter`s and gather them in a list, and then use it to produce lists of number of occurrences of every element in `l` in the given order
``````In [12]: counters = [Counter(l) for l in d1.values()]