D = fdesign.lowpass(‘Fp,Fst,Ap,Ast’,0.2,0.25,1,60);
Hd = design(D,’equiripple’,’StopbandShape’,’linear’,’StopbandDecay’,20);

Why does the above example, which is provided as one of exmaples of fdesign.lowpass, generate the following error messages?

Error using fdesign.abstracttype/equiripple (line 15)
‘StopbandShape’ is not a valid design option for EQUIRIPPLE.

Error in fdesign.abstracttype/superdesign (line 134)
Hd = feval(method, this, varargin{:},sysObjArgsDesign{:});

Error in fdesign.abstracttype/design (line 17)
varargout{1} = superdesign(this, varargin{:});

Any suggestion to make it work.D = fdesign.lowpass(‘Fp,Fst,Ap,Ast’,0.2,0.25,1,60);
Hd = design(D,’equiripple’,’StopbandShape’,’linear’,’StopbandDecay’,20);

Why does the above example, which is provided as one of exmaples of fdesign.lowpass, generate the following error messages?

Error using fdesign.abstracttype/equiripple (line 15)
‘StopbandShape’ is not a valid design option for EQUIRIPPLE.

Error in fdesign.abstracttype/superdesign (line 134)
Hd = feval(method, this, varargin{:},sysObjArgsDesign{:});

Error in fdesign.abstracttype/design (line 17)
varargout{1} = superdesign(this, varargin{:});

Any suggestion to make it work. D = fdesign.lowpass(‘Fp,Fst,Ap,Ast’,0.2,0.25,1,60);
Hd = design(D,’equiripple’,’StopbandShape’,’linear’,’StopbandDecay’,20);

Why does the above example, which is provided as one of exmaples of fdesign.lowpass, generate the following error messages?

Error using fdesign.abstracttype/equiripple (line 15)
‘StopbandShape’ is not a valid design option for EQUIRIPPLE.

Error in fdesign.abstracttype/superdesign (line 134)
Hd = feval(method, this, varargin{:},sysObjArgsDesign{:});

Error in fdesign.abstracttype/design (line 17)
varargout{1} = superdesign(this, varargin{:});

Any suggestion to make it work. fdesign.lowpass MATLAB Answers — New Questions

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