How to calculate percentage change sum (Mean) by group

[SriRajesh]

Hi,

I have below DataFrame:

A 1.2  3.6
B 2.6  3.8 
A 1.5  2.1
B 2.0  2.9
C 2.4  3.5
H 4.1  2.9
C 5.9  9.3
A 2.9  8.3
B 8.7  5.6
H 2.9  7.3
H 3.6  1.9
B 2.3  1.0
A 7.1  2.3

I use blow code:

import pandas as pd

d = {'col1': ['B','A','B','C','H','C','A','B','H','H','B','B'],'col2': [2.6,1.5,2.0,2.4,4.1,5.9,2.9,8.7,2.9,3.6,2.3,2.3], 'col3': [3.8,2.1,2.9,3.5,2.9,9.3,8.3,5.6,7.3,1.9,1,1]}
df = pd.DataFrame(data=d)
df_avg=df.groupby(['col1']).mean() # this line works
df_pct=df.groupby(['col1']).pct_change.sum()

AttributeError: 'function' object has no attribute 'sum'

[snippsat]

pct_change is a function(),so try pct_change().sum().

[SriRajesh]

I modified my code, it works, but I need the output by group.

df_pct=df.groupby(['col1']).pct_change().sum()

The above line of code does only giving the pct_change sum by column (but I want to by column & by group).

The below output is of: df_avg=df.groupby(['col1']).mean()

col1	col2	col3
A	    2.20	5.20
B	    3.57	2.86
C	    4.15	6.40
H	    3.50	4.03

Similarly I want pct_change().sum() by group

[SriRajesh]

df_pct=df.groupby(['col1']).pct_change().sum() 

The above line of code does not giving the "percentage change sum" of each column by group. How to get "percentage change sum" or "percentage change mean" of each column by group.