filter df according to column values code example

Example 1: pandas count values by column

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

Example 2: filter df by column value

# does year equals to 2002?
# is_2002 is a boolean variable with True or False in it
>is_2002 =  gapminder['year']==2002
>print(is_2002.head())
0    False
1    False
2    False
3    False
4    False