User`s guide

1 Data Processing
Constructing an iddata Object for Time-Domain Data
Use the follow ing sy ntax to create a time-d omain iddata object data:
data = iddata(y,u,Ts)
You can also specify additional properties, as follows:
data = iddata(y,u,Ts,'Property1',Value1,...,'Propert yN',ValueN)
For more information about accessing obje ct properties, see “iddata
Properties” on page 1-50.
In this example,
Ts isthesamplingtime,orthetimeinterval,between
successive data samples. For uniformly sampled data,
Ts is a scalar valu e
equal to the sampling interval of your experiment. The default time unit is
seconds, but you can specify any unit string using the
TimeUnit property.
For more information about
iddata time properties, see “Modifying Time
and Frequency Vectors” on page 1-59.
For nonuniformly sampled data, specify
Ts as [], and set the value of the
SamplingInstants property as a column vector containing i ndividual tim e
values. For example:
data = iddata(y,u,Ts,[],'SamplingInstants',TimeVecto r)
Where TimeVector represents a vector of time values.
Note You can modify the property SamplingInstants by setting it to a new
vector with the length equal to the number of d ata samples.
To represent time-series data, use the following sy ntax:
ts_data = iddata(y,[],Ts)
where y is the output data, [] indicates empty input data, and Ts is the
sampling interval.
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