Shift data sequences
Datas = nkshift(Data,nk) Datas = nkshift(___,Name,Value)
nk is a row vector with the same length as
the number of input channels in
Name-value pair arguments specify additional model arguments. The available arguments consist of:
OutputNameare the input and output channel names. Use these arguments especially when
Datais a timetable that has more variables than you want to use or when the input and output variables are intermixed. Also use
OutputNameto identify the output channels when the timetable contains more than one output variable. Otherwise, the software interprets only the last variable an output channel.
For example, specify the input and output signal variable names using
Datas = nkshift(Data,'InputName',["u1","u3"],'OutputName',"y1")You can use this syntax with any of the previous input-argument combinations.
TimeUnitprovide the sample time and time units.
Datas, which has the same form as
Data, contains data in
which the input channels in
Data have been shifted according to
nk. A positive value of
nk(ku) means that
input channel number
ku is delayed
nkshift supports both frequency- and time-domain
data. For frequency-domain data it multiplies with einkωT to
obtain the same effect as shifting in the time domain. For continuous-time
frequency-domain data (
Ts = 0),
be interpreted as the shift in seconds.
nkshift lives in symbiosis with the
of linear identified models:
m1 = ssest(dat,4,'InputDelay',nk)
is related to
m2 = ssest(nkshift(dat,nk),4);
the same models, but
m1 stores the delay information
and uses this information when computing the frequency response, for
example. When using
m2, the delay value must be
accounted for separately when computing time and frequency responses.
Version HistoryIntroduced before R2006a
R2022b: Time-domain estimation data is accepted in the form of timetables and matrices
Most estimation, validation, analysis, and utility functions now accept time-domain
input/output data in the form of a single timetable that contains both input and output data
or a pair of matrices that contain the input and output data separately. These functions
continue to accept
iddata objects as a data source as well, for
both time-domain and frequency-domain data.