count the frequency that a value occurs in a dataf

Question

I have a dataset

|category|
cat a
cat b
cat a

I'd like to be able to return something like (showing unique values and frequency)

category | freq |
cat a       2
cat b       1

Answer 1

df.category.value_counts()

This short little line of code will give you the output you want.

Answer 2

df.apply(pd.value_counts).fillna(0)

value_counts - Returns object containing counts of unique values

apply - count frequency in every column. If you set axis=1, you get frequncy in every row

fillna(0) - make output more fancy. Changed NaN to 0