beliav...@aol.com.dmarc.invalid wrote: > I am going to read a multivariate time series from a CSV file that looks > like > > Date,A,B > 2014-01-01,10.0,20.0 > 2014-01-02,10.1,19.9 > ... > > The numerical data I will store in a NumPy array, since they are more > convenient to work with than lists of lists. What are the advantages and > disadvantages of storing the symbols [A,B] and dates > [2014-01-01,2014-01-02] as lists vs. NumPy arrays?
If you don't mind the numpy dependency I can't see any disadvantages. You might also have a look at pandas: >>> ts = pandas.read_csv(io.StringIO("""\ ... Date,A,B ... 2014-01-01,10.0,20.0 ... 2014-01-02,10.1,19.9 ... """), parse_dates=[0]) >>> ts Date A B 0 2014-01-01 00:00:00 10.0 20.0 1 2014-01-02 00:00:00 10.1 19.9 >>> ts["A"] 0 10.0 1 10.1 Name: A, dtype: float64 >>> ts["Date"] 0 2014-01-01 00:00:00 1 2014-01-02 00:00:00 Name: Date, dtype: datetime64[ns] >>> ts["Date"][0] Timestamp('2014-01-01 00:00:00', tz=None) >>> pylab.show(ts.plot(x="Date", y=["A", "B"])) -- https://mail.python.org/mailman/listinfo/python-list