Node Class

This is a class in the Object Oriented Programming (OOP) paradigm that defines node objects in the LESM (Linear Elements Structure Model) program.

A node is a joint between two or more elements, or any element end, used to discretize the model. It is always considered as a tri-dimensional entity which may have applied loads or prescribed displacements towards one of its six degrees of freedom.

Contents

Class definition

Definition of super-class Node as a handle class.

classdef Node < handle

Public attributes

    properties (SetAccess = public, GetAccess = public)
        id = 0;            % identification number
        coord = [];        % vector of coordinates on global system [X Y Z]
        ebc = [];          % vector of essential boundary condition flags [dx dy dz rx ry rz]
        nodalLoad = [];    % vector of applied load components [fx fy fz mx my mz]
        prescDispl = [];   % vector of prescribed displacement values [dx dy dz rx ry rz]
    end

Constructor method

    methods
 
        %------------------------------------------------------------------
        function node = Node(id,coord,ebc,nodalLoad,presDispl)
            if (nargin > 0)
                node.id = id;
                node.coord = coord;
                node.ebc = ebc;
                node.nodalLoad = nodalLoad;
                node.prescDispl = presDispl;
            end
        end
    end

Public methods

    methods
 
        %------------------------------------------------------------------
        % Counts total number of elements and number of hinged elements
        % connected to a node.
        % Output:
        %  tot: total number of elements connected to a node
        %  hng: number of hinged elements connected to a node
        % Input arguments:
        %  drv: handle to an object of the Drv class
        function [tot,hng] = elemsIncidence(node,drv)
            include_constants;

            % Initialize values
            tot = 0;
            hng = 0;

            for e = 1:drv.nel
                % Check if initial node of current element is the target one
                if drv.elems(e).nodes(1).id == node.id
                    tot = tot + 1;
                    if drv.elems(e).hingei == HINGED_END
                        hng = hng + 1;
                    end

                % Check if final node of current element is the target one
                elseif drv.elems(e).nodes(2).id == node.id
                    tot = tot + 1;
                    if drv.elems(e).hingef == HINGED_END
                        hng = hng + 1;
                    end
                end
            end
        end

 
        %------------------------------------------------------------------
        % Cleans data structure of a Node object.
        function clean(node)
            node.id = 0;
            node.coord = [];
            node.ebc = [];
            node.nodalLoad = [];
            node.prescDispl = [];
        end
    end

end

Published with MATLAB® R2017a