Pandas series sort by month index

Question

Dec    47
Nov    36
Oct    14
Sep     2
Jan     2
Aug     2
May     1
Apr     1
Jun     1
Jul     1
Feb     1
Name: date, dtype: int64

I'm tring to sort the above series whose index column is month, by month. However instead of sorting by month's calendar order the sort function is sorting by dictionary order of the month name. How can I sort the above correctly? Guess I have to specify that the index type is month and not string. Any help is appreciated. Code snippet below.

import calendar
movies = release_dates[release_dates.title.str.contains('Christmas') & (release_dates.country=='USA')]
movies = movies.date.dt.month.apply(lambda x: calendar.month_abbr[x])
counts = movies.value_counts()
counts

Answer 1

You can use sorted CategoricalIndex with sort_index:

cats = ['Jan', 'Feb', 'Mar', 'Apr','May','Jun', 'Jul', 'Aug','Sep', 'Oct', 'Nov', 'Dec']
df.index = pd.CategoricalIndex(df.index, categories=cats, ordered=True)
df = df.sort_index()

print (df)
     date
Jan     2
Feb     1
Apr     1
May     1
Jun     1
Jul     1
Aug     2
Sep     2
Oct    14
Nov    36
Dec    47

Or use DataFrame.reindex - but if some value is missing add NaNs rows:

df = df.reindex(cats)