Pandas more
df.iloc[:, 4:10].sum(axis=1) # rearrange order of columns cols = list(df.columns) df = df[ cols[0:4], cols[-1], cols[4:20] ] to_csv('file.csv', index=False) read_csv(filename, delimiter='\t') to_csv(filename, sep='\t') # after filtering out some rows: df = df.reset_index() df.reset_index(drop=True, inplace=True) filter with df.loc[ ~df['Name'].str.contains('substring') ] can also have regex=True parameter # replace values df[ df['Name'] == 'old', 'Name' ] = 'new'