Python - Pandas dataframe - iteration through a column -


i have pandas dataframe , add empty column (named nb_trades). fill new column 5 5 increment. should column values 5 10 15 20 ...

doing below code assign same value (last value of i) in whole column , that's not wanted:

big_df["nb_trade"]='0' in range(big_df.shape[0]):     big_df['nb_trade']=5*(i+1)

can me?

use range or np.arrange:

df = pd.dataframe({'a':[1,2,3]}) print (df)    0  1 1  2 2  3  df['new'] = range(5, len(df.index) * 5 + 5, 5) print (df)     new 0  1    5 1  2   10 2  3   15 
df['new'] = np.arange(5, df.shape[0] * 5 + 5, 5) print (df)     new 0  1    5 1  2   10 2  3   15

solution of john galt comment:

df['new'] = np.arange(5, 5*(df.shape[0]+1), 5) print (df)     new 0  1    5 1  2   10 2  3   15

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