Error defining single class property in Enumeration Class

Hello everyone, I am struggling to find how to make this work in MATLAB.

I have an Enumeration Class, which has its enumerators plus a single class property which is a function pointer to some (same class) Static Functions. In other words, depending on the enumerator value, the function pointer will point to its related function, so that I can then have an ```evaluate()``` function which calls the function pointer under the hood.

Here is the idea:

classdef PSDType < handle

enumeration
	DAVENPORT (PSDType.DavenportPSD)
	VON_KARMAN (PSDType.VonKarmanPSD)
	KAIMAL (PSDType.KaimalPSD)
	EUROCODE (PSDType.EurocodePSD)
	ORNSTEIN_UHLENBECK (PSDType.OU_PSD)
end

properties (Access = private)
	func_ptr function_handle
end

methods (Access = public)
    function S = evaluate(this, varargin)
        try
            S = this.func_ptr(varargin{:});
        catch ex
            warning('\n%s', ...
                '@PSDType.evaluate: exception evaluating PSD');
            getReport(ex);
        end
    end
end

methods (Static = true)
    ... here static methods to point to
end

end

However, once I run, as soon as it load into memory the Class which has as one of its member functions this Enumeration Class instance, I get this error

Invalid default value for property 'PSD_TYPE' in class 'WindData':
Not enough input arguments.

memb PSDType = PSDType.DAVENPORT  % (default initialisation in class member instance)

I even added the Class constructor:

function this = PSDType(f_ptr)
	this.func_ptr = f_ptr;
end

with no changes.

What do I do wrong?

Thanks a lot for your answers!

Answer 1

[Michele Esposito Marzino]

I finally found I was missing the "@" operator when assigning function to point to. @chrisw23 thanks for yor answer, I would bet it works, but I wanted to avoid the switch statement.

This worked fine finally:

classdef PSDType < handle

enumeration
	DAVENPORT (@PSDType.DavenportPSD)
	VON_KARMAN (@PSDType.VonKarmanPSD)
	KAIMAL (@PSDType.KaimalPSD)
	EUROCODE (@PSDType.EurocodePSD)
	ORNSTEIN_UHLENBECK (@PSDType.OU_PSD)
end


properties (Access = private)
	psd_func_ptr function_handle
end


methods (Access = public)

	function this = PSDType(f_ptr)
		this.psd_func_ptr = f_ptr;
	end

    function PSDeval = evaluate(this, varargin)
        
        ...

		PSDeval = this.psd_func_ptr(varargin{:});
	end % evaluate()

end
end

Answer 2

[chrisw23]

classdef PSDType

enumeration

DAVENPORT

VON_KARMAN

KAIMAL

EUROCODE

ORNSTEIN_UHLENBECK

end

methods (Access = public)

function obj = PSDType()

% constructor

end

function s = evaluate(obj, varargin)

s = [];

switch obj

case PSDType.DAVENPORT

s = obj.callDavenPort(varargin);

case PSDType.VON_KARMAN

case PSDType.KAIMAL

case PSDType.EUROCODE

case PSDType.ORNSTEIN_UHLENBECK

end

end

end

methods (Access = 'private')

function s = callDavenPort(obj,varargin)

s = "evalDavenPort";

end

end

end

How about this ?

PSDType.DAVENPORT.evaluate

"evalDavenPort"