Initial Position of PSO

Hi There,

How do I initiate an initial position for PSO when moving from position to another.. I'm using class below to initiate my particles.

classdef sample_particle

    properties
        swarm = [];
        index = 1;
    end

    methods
        function [ obj ] = sample_particle( varargin )
            % set the position of the initial swarm
            for i = 1 : 8
                for j = 1 : 8
                    obj.swarm(obj.index, 1, 1) = i;
                    obj.swarm(obj.index, 1, 2) = j;
                    obj.index = obj.index + 1;
                end
            end
            obj.swarm(:,2,:) = 0;                       % set initial velocity for particles
            obj.swarm(:,4,1) = inf;                     % set the best value so far
        end
    end
end

and objective function and end point

function [ z ] = objfcn_02( x )
x1=x(:,1);      % starting X position
y1=x(:,2);      % starting y position
x2=10;         % ending X position
y2=10;         % ending y position
z = sqrt((x1-x2).^2+(y1-y2).^2);
end