How do I hstack EVERY 50 rows to a long row in a dataframe?-CodePudding

I have a data frame of 300 rows x 6 columns. I want to hstack every 50 rows x 6 columns to 1 row x 300 columns. Is there any way to do that?

CodePudding user response：

you can use this approach:

example data

df1 = pd.DataFrame([['C45','AB','ZU'],['C45','ZO','RE'],
    ['C67','RT','FG',],['C78','TZ','GH']], columns=['id1','id2','id3'])

it looks like this:

    id1 id2 id3
0   C45 AB  ZU
1   C45 ZO  RE
2   C67 RT  FG
3   C78 TZ  GH

command

N = 2
pd.concat([df1.iloc[np.arange(i,len(df1),N)].reset_index(drop=True) 
    for i in range(N)], axis=1)

the result looks like this:

id1 id2 id3 id1 id2 id3
0   C45 AB  ZU  C45 ZO  RE
1   C67 RT  FG  C78 TZ  GH

you may also add rename after reset_index to avoid duplicate column names.