How to get a list of index values after groupby().mean() in pandas?

Question

I am stuck with this. I would like to get a list of name from the following, a result of groupby().mean() with the application of pandas DataFrame. Most specifically, I would like to get ["John", "Mary", "Suzan", "Eric"] .

      score
name       
John   85.0
Mary   86.5
Suzan  90.0
Eric   100.0

The result of the above is means , which comes from the following:

data = pandas.DataFrame({"name": names, "score": scores})
means = data.groupby("name").mean()

As now I have means , I would like to get a list of names from 'means' - ["John", "Mary", "Suzan", "Eric"] . Is this achievable?

Answer 1

Just look at the index if you have an Index. If you have a MultiIndex, see @jezrael's answer with get_level_values .

means.index.tolist()

Answer 2

You can use:

print (list(means.index))
['John', 'Mary', 'Suzan', 'Eric']

Another better solution is use Series.unique and omit groupby :

print (data.name.unique())
['John' 'Mary' 'Suzan' 'Eric']