Fill different pandas columns based upon a list-CodePudding

I want to fill multiple columns with different values.

I have a df that looks as such:

df
    'A'   'B'    'C'
0   1     dog    red
1   5     cat    yellow
2   4     moose  blue

I would like to overwrite the columns based upon list values and so would look like this:

overwrite = [0, cat, orange]

    df
    'A'   'B'    'C'
0   0     cat    orange
1   0     cat    orange
2   0     cat    orange

Is there an easy way to do this?

Thanks

CodePudding user response：

Simply assign the value to the columns, they will be broadcasted:

overwrite = [0, 'cat', 'orange']
df[['A', 'B', 'C']] = overwrite

Or maybe, if the overwrite list can be shorter than the number of columns:

df.iloc[:, :len(overwrite)] = overwrite

# or
df[df.columns[:len(overwrite)]] = overwrite

Output:

   A    B       C
0  0  cat  orange
1  0  cat  orange
2  0  cat  orange

CodePudding user response：

Use DataFrame.assign with dictionary to overwrite the columns based upon list:

df = df.assign(**dict(zip(df.columns, overwrite)))
print (df)
   'A'  'B'     'C'
0    0  cat  orange
1    0  cat  orange
2    0  cat  orange

Or create DataFrame by constructor - values are not overwritten, but created new one with same columns and index like original DataFrame:

df = pd.DataFrame([overwrite], index=df.index, columns=df.columns)
print (df)
   'A'  'B'     'C'
0    0  cat  orange
1    0  cat  orange
2    0  cat  orange

CodePudding user response：

Try this...

df = pd.DataFrame({'A':[1,2,3],'B':['cat','dog','bird']})
overwrite = [0,'Elk']
for index,row in df.iterrows():
    df.iloc[index,:] = overwrite
df