Add column to dataframe with constant value
I have an existing dataframe which I need to add an additional column to which will contain the same value for every row.
Existing df:
Date, Open, High, Low, Close
01-01-2015, 565, 600, 400, 450
New df:
Name, Date, Open, High, Low, Close
abc, 01-01-2015, 565, 600, 400, 450
I know how to append an existing series / dataframe column. But this is a different situation, because all I need is to add the 'Name' column and set every row to the same value, in this case 'abc'.
Answer
df['Name']='abc' will add the new column and set all rows to that value:
In [79]:
df
Out[79]:
Date, Open, High, Low, Close
0 01-01-2015, 565, 600, 400, 450
In [80]:
df['Name'] = 'abc'
df
Out[80]:
Date, Open, High, Low, Close Name
0 01-01-2015, 565, 600, 400, 450 abc