Several time series to DataFrame
问题 I have problem merging several time series to a common DataFrame. The example code I'm using: import pandas import datetime import numpy as np start = datetime.datetime(2001, 1, 1) end = datetime.datetime(2001, 1, 10) dates = pandas.date_range(start, end) serie_1 = pandas.Series(np.random.randn(10), index = dates) start = datetime.datetime(2001, 1, 2) end = datetime.datetime(2001, 1, 11) dates = pandas.date_range(start, end) serie_2 = pandas.Series(np.random.randn(10), index = dates) start =