>Try this instead: > > > dict[name] = pd.concat([dict[name], values])
OK. That fixed the problem, however, I see that they are concatenated vertically. How can I change that to horizontal? The printed dictionary in the end looks like {'dummy': Value M1 0 M2 0 M3 0, 'K1': Value 0 10 1 5 2 10 6 2 7 2 8 2, 'K2': Value 3 20 4 10 5 15} For K1, there should be three rows and two columns labeled as Value. Regards, Mahmood -- https://mail.python.org/mailman/listinfo/python-list