Search class

Contents

Description

This is a handle heterogeneous super-class for the definition of search algorithms.

A search algorithm is invoked frequently during the simulation to identify the neighbours of each particle.

Depending on the interaction models adopted, a cutoff distance is assumed for defining a neighbour (contact neighbours have a cutoff distance of zero).

This super-class defines abstract methods that must be implemented in the derived sub-classes:

classdef Search < handle & matlab.mixin.Heterogeneous

Constant values

    properties (Constant = true, Access = public)
        % Types of search algorithm
        SIMPLE_LOOP = uint8(1);
        VERLET_LIST = uint8(2);
    end

Public properties

    properties (SetAccess = public, GetAccess = public)
        % Identification
        type uint8   = uint8.empty;     % flag for type of search algorithm
        done logical = logical.empty;   % flag for identifying if search has been done in current time step

        % Parameters
        freq   uint32 = uint32.empty;   % search frequency (in steps)
        cutoff double = double.empty;   % cut-off neighbour distance (radius multiplication factor)

        % Base object for common interactions
        b_interact Interact = Interact.empty;   % handle to object of Interact class for all interactions
    end

Constructor method

    methods
        function this = Search(type)
            if (nargin > 0)
                this.type = type;
            end
        end
    end

Default sub-class definition

    methods (Static, Access = protected)
        function defaultObject = getDefaultScalarElement
            defaultObject = Search_SimpleLopp;
        end
    end

Abstract methods: implemented in derived sub-classes

    methods (Abstract)
        %------------------------------------------------------------------
        setDefaultProps(this);

        %------------------------------------------------------------------
        initialize(this,drv);

        %------------------------------------------------------------------
        execute(this,drv);
    end

Public methods

    methods
        %------------------------------------------------------------------
        function kin = createPPKinematic(~,p1,dir,dist,separ)
            % Only sphere-sphere or cylinder-cylinder interactions
            switch p1.type
                case p1.SPHERE
                    kin = BinKinematics_SphereSphere(dir,dist,separ);
                case p1.CYLINDER
                    kin = BinKinematics_CylinderCylinder(dir,dist,separ);
            end
        end

        %------------------------------------------------------------------
        function type = pwInteractionType(~,p,w)
            switch p.type
                case p.SPHERE
                    switch w.type
                        case w.LINE
                            type = 1;
                        case w.CIRCLE
                            type = 2;
                    end
                case p.CYLINDER
                    switch w.type
                        case w.LINE
                            type = 3;
                        case w.CIRCLE
                            type = 4;
                    end
            end
        end
    end

end

Published with MATLAB® R2019b