how to count a column in pandas code example

Example 1: pandas get count of column

df['column_name'].value_counts()

Example 2: pandas count rows in column

>>> df.count(axis='columns')
0    3
1    2
2    3
3    3
4    3
dtype: int64

Example 3: pandas count values by column

df = pd.DataFrame({'a':list('abssbab')})
df.groupby('a').count()