Re-ordering columns in pandas dataframe based on column name [duplicate]

I have a dataframe with over 200 columns. The issue is as they were generated the order is

['Q1.3','Q6.1','Q1.2','Q1.1',......]

I need to re-order the columns as follows:

['Q1.1','Q1.2','Q1.3',.....'Q6.1',......]

Is there some way for me to do this within Python?

Solution 1:

df = df.reindex(sorted(df.columns), axis=1)

This assumes that sorting the column names will give the order you want. If your column names won't sort lexicographically (e.g., if you want column Q10.3 to appear after Q9.1), you'll need to sort differently, but that has nothing to do with pandas.

Solution 2:

You can also do more succinctly:

df.sort_index(axis=1)

Make sure you assign the result back:

df = df.sort_index(axis=1)

Or, do it in-place:

df.sort_index(axis=1, inplace=True)

Solution 3:

You can just do:

df[sorted(df.columns)]

Edit: Shorter is

df[sorted(df)]