User`s guide

Preparing Time-Series Data
Preparing Time-Series Data
Before you can estimate models for time-s eries data, you must import your
data into the MATLAB software. You can estimate models from either
time-domain and frequency-domain data. For information about which
variables you need to represe nt tim e-s eries data, see “Importing Time-Series
Data into MATLAB” on page 1-7.
For more information about preparing data for modeling, see “Ways to Process
Data for System Identification” on page 1-2.
If your data is already in the MATLAB workspace, you can import it d irectly
into the System Identification Tool GUI. If you prefer to work at the command
line, you must represent the data as a System Identificatio n Toolbox data
object instead.
In the System Iden tification Tool GUI. When you import scalar or
multiple-outpu t time series data in to the GUI, leave the Inpu t field empty.
For more info rmation about importing data, see “Re presenting Data in the
GUI” on page 1-13.
At the command line. To repres ent a time series vector or a matrix
s as an
iddata object, use the following syntax:
y = iddata(s,[],Ts);
s
contains as many columns as there are measured outputs. For time-dom ain
data, set
Ts to the sampling i nterval. For continuous-time frequency domain
data, set
Ts to 0.
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