Example 1: count values pandas
>>> index = pd.Index([3, 1, 2, 3, 4, np.nan])
>>> index.value_counts()
3.0 2
4.0 1
2.0 1
1.0 1
dtype: int64
Example 2: pandas get count of column
df['column_name'].value_counts()
Example 3: count na pandas
>>> df = pd.DataFrame({"Person":
... ["John", "Myla", "Lewis", "John", "Myla"],
... "Age": [24., np.nan, 21., 33, 26],
... "Single": [False, True, True, True, False]})
>>> df
Person Age Single
0 John 24.0 False
1 Myla NaN True
2 Lewis 21.0 True
3 John 33.0 True
4 Myla 26.0 False
df.count()
Person 5
Age 4
Single 5
dtype: int64
Example 4: Counter to df pandas
from collections import Counter
d = Counter({'fb_view_listing': 76, 'fb_homescreen': 63, 'rt_view_listing': 50, 'rt_home_start_app': 46, 'fb_view_wishlist': 39, 'fb_view_product': 37, 'fb_search': 29, 'rt_view_product': 23, 'fb_view_cart': 22, 'rt_search': 12, 'rt_view_cart': 12, 'add_to_cart': 2, 'create_campaign': 1, 'fb_connect': 1, 'sale': 1, 'guest_sale': 1, 'remove_from_cart': 1, 'rt_transaction_confirmation': 1, 'login': 1})
df = pd.DataFrame.from_dict(d, orient='index').reset_index()
Example 5: pandas count values by column
df = pd.DataFrame({'a':list('abssbab')})
df.groupby('a').count()
Example 6: pandas count
>>> df.set_index(["Person", "Single"]).count(level="Person")
Age
Person
John 2
Lewis 1
Myla 1