How to apply string methods to multiple columns of a dataframe

Question

I have a dataframe with multiple string columns. I want to use a string method that is valid for a series on multiple columns of the dataframe. Something like this is what I w

Answer 1

Function rstrip working with Series so is possible use apply:

df = df.apply(lambda x: x.str.rstrip('f'))

Or create Series by stack and last unstack:

df = df.stack().str.rstrip('f').unstack()

Or use applymap:

df = df.applymap(lambda x: x.rstrip('f'))

Last if need apply function to some columns:

#add columns to lists
cols = ['A']
df[cols] = df[cols].apply(lambda x: x.str.rstrip('f'))
df[cols] = df[cols].stack().str.rstrip('f').unstack()
df[cols] = df[cols].stack().str.rstrip('f').unstack()