User`s guide

Importing Data into the MATLAB
®
Workspace
Impor ting Data into the MATLAB Wo rkspace
In this section...
“Types of Data You Can Model” on page 1-5
“Support for Data with Uniform and Nonuniform Sampling Intervals” on
page 1-6
“Importing Time-Domain Data into MATLAB” on page 1-6
“Importing Time-Series Data into M ATLA B” on page 1-7
“Importing Frequency-Domain Data into MATLAB” on page 1-8
“Importing Frequency-Response Data into MATLAB” on page 1-10
Types of Data You Can Model
For linear models, y ou can identify bo th time- and frequency-domain data
with single or multiple inputs and outputs. Time-domain data can be either
real or complex.
For nonlinear mode ls, this toolbox sup po rts only time-dom ain da ta.
Time-domain data is one or m ore input v ariables u(t) and one or more output
variables y(t), s ampled as a function of time.
Frequency-domain data is the Fourier transform of the input a nd output
time-domain signals.
Frequency-response data,alsocalledfrequency-function data,represents
complex frequency-response values for a linear system characterized by its
transfer function G. You can measure frequency-re sponse data value s directly
using a spectrum analyzer, for example.
Time-series data, which contains one or more outputs y(t) and no measured
input, can be time-domain or frequency-domain data.
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