pandas dataframe group and sort by weekday

Question

I have pandas DataFrame that includes Day of Week column.

df_weekday = df.groupby(['Day of Week']).sum()
df_weekday[['Spent', 'Clicks', 'Impressions']].plot(figsize=(16,6), subplots=True);

plot the DataFrame displays 'Day of Week' in alphabetical order: 'Friday', 'Monday', 'Saturday', 'Sunday' , 'Tuesday' , 'Thursday', 'Wednesday'.

how can i sort and display df_weekday in proper weekday order 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday'. ?

Answer 1

You can use ordered catagorical first:

cats = [ 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday']

df['Day of Week'] = df['Day of Week'].astype('category', categories=cats, ordered=True)

In pandas 0.21.0+ use:

from pandas.api.types import CategoricalDtype
cat_type = CategoricalDtype(categories=cats, ordered=True)
df['Day of Week'] = df['Day of Week'].astype(cat_type)

Or reindex:

df_weekday = df.groupby(['Day of Week']).sum().reindex(cats)