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Class: sdo.requirements.GainPhaseMargin
Package: sdo.requirements

Evaluate gain and phase margin bounds for linear system


c = evalRequirement(req,lin_sys)


c = evalRequirement(req,lin_sys) evaluates whether a linear system satisfies the specified gain and phase margin bounds. The gain and phase margins are computed using the feedback sign specified in the FeedbackSign property of req.

Input Arguments


sdo.requirements.GainPhaseMargin object.


Linear system (tf, ss, zpk, frd, genss, or genfrd).

Output Arguments


  • Signed distance of the computed gain and phase margins to the bound if the Type property of req is >= or ==.

    Signed distance to the gain margin bound appear before the signed distance to the phase margin bound. Negative values indicate that the bound is satisfied while positive values indicate the bound is violated. Unstable loops return positive values. When ==, any number other than 0 indicates that the bound is not satisfied.

  • Negative of the gain and phase margins such that minimizing the values maximizes the margins if the Type property of req is 'max. Unstable loops return positive values.


Evaluate gain and phase margin requirements.

 req = sdo.requirements.GainPhaseMargin;
 sys = tf(0.5,[1 3 3 1]);
 c = evalRequirement(req,sys);

c is negative, which indicates that the system satisfies the gain and phase margin requirement.

See Also

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