How to do partial operations on python DataFrames

Question

I want to subtract the mean of each column of my DataFrame for each part of it (ie for each index value "hostname"). I tried this :

for host in hostnames:
  df_temp = df.loc[host]
  df_temp = df_temp.subtract(df_temp.mean(axis=0))
  df.loc[host] = df_temp

... but it is taking forever (even for one loop).

Thank you for your help !

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score 0 · Answer 1 · answered Feb 11 '18 at 20:39

0

Found it : Didn't know about "level" parameter

df - df.mean(axis=0,level=0)

answered Feb 11 '18 at 20:39

Maxime

Hmmm, solution is working for you, but really hard answering with no data ;) – jezrael Feb 11 '18 at 20:43
Sorry about that, I will try to ask better question next time – Maxime Feb 11 '18 at 21:00
No problem, it is simple - sample data, expected output and what you try ;) Good luck! – jezrael Feb 11 '18 at 21:02

1 Answers1