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ToDiscreteTimeModel

ToDiscreteTimeModel
gives the discrete-time approximation with sampling period of the continuous-time StateSpaceModel or TransferFunctionModel object sys.
ToDiscreteTimeModel
gives the discrete-time approximation of the TransferFunctionModel object tf, using z as the Z-transform variable.
  • The setting Method->{m, "StateSpaceConversion"->Automatic} computes the approximation using the transfer-function representation, except for the and methods.
A discrete-time approximation of a continuous-time system:
A discrete-time approximation of a continuous-time system:
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Convert a continuous-time transfer-function model to the discrete-time domain:
Convert a continuous-time state-space model to discrete time:
Convert a multiple-input, multiple-output system to discrete time:
Convert a symbolic system:
By default, the approximation is based on the bilinear transformation:
Specify the desired approximation method:
Compare the various approximation methods:
An approximation that preserves the transmission at the specified frequency:
Various approximations to a fourth-order Butterworth low-pass filter:
Method does not necessarily give a stable approximation of a stable system:
The setting Method gives a stable approximation only if the critical frequency is less than the Nyquist frequency:
All other approximations give a stable system if the continuous-time system is stable:
ToContinuousTimeModel is essentially the inverse of ToDiscreteTimeModel:
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