python - Pandas replace function & "Returning a view versus a copy" -


i'm trying use replace function on data frame, , know problem i'm modifying copy , should use .loc or .ix return view instead of copy, i'm total beginner , struggled bit pandas documentation on this.

i tried following:

df.replace(df[(df.group_id=='12')]['clicks'], df2, inplace=true)

which modifies copy, , doesn't change values in df.

i'm not sure how can use .ix in case. tried

df.replace(df[(df.group_id=='12')].ix[:,'clicks'], df2, inplace=true)

but doesn't work.

thanks lot in advance.


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