Randomly insert NA’s values in a pandas dataframe

Here’s a way to clear exactly 10% of cells (or rather, as close to 10% as can be achieved with the existing data frame’s size).

import random
ix = [(row, col) for row in range(df.shape[0]) for col in range(df.shape[1])]
for row, col in random.sample(ix, int(round(.1*len(ix)))):
    df.iat[row, col] = np.nan

Here’s a way to clear cells independently with a per-cell probability of 10%.

df = df.mask(np.random.random(df.shape) < .1)