How to sum unique values of dataframe

Asked Jun 18 '19 at 16:53

Active Jun 18 '19 at 16:54

Viewed 21 times

I have a dataframe:

df = pd.DataFrame([{'y': 2019, 'pop': 234}, {'y': 2018, 'pop': 23}, {'y': 2017, 'pop': 2444}, {'y': 2018, 'pop': 12}, {'y': 2019, 'pop': 22}])

I want to create a new dataframe where the pop is summed based on the year:

years = df['y'].unique()    
df2 = pd.DataFrame([{'y': 2019, 'pop': 256}, {'y': 2018, 'pop': 35}, {'y': 2017, 'pop': 2444}])

edited Jun 18 '19 at 16:54

asked Jun 18 '19 at 16:53

Evan Brittain

look in to --> https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.groupby.html – gold_cy Jun 18 '19 at 16:55
1

`df.groupby(['y']).sum()` – vurmux Jun 18 '19 at 16:55
1

Also: `df.pivot_table(values='pop', index='y', aggfunc='sum')` – Quang Hoang Jun 18 '19 at 16:56

0 Answers0