Undefined function 'abc' for input arguments of type 'double'.

I'm trying to create a flowfield class, but am getting errors when I'm creating functions

just calling

abc(n);

gets me an error

function abc(obj,n)
obj.state=n;
end

Full code

classdef flowfield < handle

    % Public properties
    properties (Access = public)
        size        int64 = [10,10];
        origin      int64 = [3,4];
        distance    double;
        direction   double;
        open_set
        current_pos;
        state;
    end

    methods (Access = public)
        
        % Constructor
        function obj = flowfield()
            open_set = queue(2);
            open_set.enqueue(obj.origin);
            obj.distance = inf(obj.size);
            obj.direction = NaN(obj.size);
            
            % Main loop
            while (~open_set.isempty)
                obj.current_pos = open_set.dequeue;
                %pos=obj.current_pos+[1,-1];
                obj.state=1;
                n=1;
                abc(n);
%                 update_node(obj.current_pos+[1,0]);
%                 update_node(obj.current_pos+[1,1]);
%                 update_node(obj.current_pos+[0,1]);
%                 update_node(obj.current_pos+[-1,1]);
%                 update_node(obj.current_pos+[-1,0]);
%                 update_node(obj.current_pos+[-1,-1]);
%                 update_node(obj.current_pos+[0,-1]);

                
            end
        end
        function abc(obj,n)
            obj.state=n;
        end
    end

    methods (Access = public)

        function update_nodea(obj, pos)
            % If out of bounds
            if ( 0>=pos(1) || pos(1)>obj.size(1) ) || ...
               ( 0>=pos(2) || pos(2)>obj.size(2) )
                return
            end
            
            new_value = obj.map(obj.current_pos) + norm(obj.current_pos, pos); % adds current distence with distence between both nodes
            if (obj.map(pos) > new_value)
                obj.map(pos) = new_value;
                obj.open_set.enqueue(pos);
            end
        end
    end
end

Answer 1

[Steven Lord]

The way you've defined your method, one or both of the inputs obj and n to your method must be an instance of the class. You're only providing one input to the function and that input is not an instance of the flowfield class, so MATLAB will not even try to call the class method.