Random Sampling of Pandas data frame (both rows and columns)

Question

I know how to randomly sample few rows from a pandas data frame. Lets say I had a data frame df, then to get a fraction of rows, I can do :

df_sample = df.sample(frac=0.007)

However what I need is random rows as above AND also random columns from the above data frame.

Df is currently 56Kx8.5k. If I want say 500x1000 where both 500 and 1000 are randomly sampled how to do this?

I think one approach would be do something like

df.columns to get a list of columns names.

Then do some random sampling of the indices of this list of columns and use that random indices to filter out remaining columns?

Answer 1

Just call sample twice, with corresponding axis parameters:

df.sample(n=500).sample(n=1000, axis=1)

For the first one, axis=0 by default. The first sampling samples lines, while the second considers columns.