df=pd.DataFrame([1,4,1,3,2,8,3,6,3,7,3,1,2,9])
I'd like to split df into a specified number of groups and sum all elements in each group. For example, dividing df into 4 groups
1,4,1,3 2,8,3,6 3,7,3,1 2,9
would result in
9
19
14
11
I could do df.groupby(np.arange(len(df))//4).sum(), but this won't work for larger dataframes
For example
df1=pd.DataFrame([1,4,1,3,2,8,3,6,3,7,3,1,2,9,1,5,3,4])
df1.groupby(np.arange(len(df1))//4).sum()
creates 5 groups instead of 4