for loop ode45 with dynamic variables

Hi I am writing a small program that can create many different particles that move up in the y-direction spread out in the x-direction. The particles interact with each other with repelling forces and so the position of each particle with reference to each other is required in the ode45 calculation. I have looked over the code many many times but I am not sure where the fault is as the solution comes up as "NaN." I have not shown constants in the code:

time_interval = 1000; %Time in microseconds
    %The number of time intervals the particle movement is divided by
    number_of_intervals = 10000/time_interval;
    
    tstart=0;
    tstop= time_interval*1e-6;

    num_of_particles = 3;
    
    w0{1} = [0;0;0;0];
    sols{1} = transpose(w0{1});
    x_adj_stable(1) = 0;
    y_adj_stable(1) = 0;
    
    break_vect(num_of_particles) = 0;
    times{1} = 0;
    
    %Initiate particle characteristics
    for particle_num = 2:num_of_particles
    w0{particle_num} = [0;0;w0{particle_num - 1}(3) + 4*1e-6;0];
    x_adj_stable(particle_num) = w0{particle_num}(3);
    y_adj_stable(particle_num) = 0;
    sols{particle_num} = transpose(w0{particle_num});
    times{particle_num} = 0;
    end

    %Event options, Identifying the time intervals within the solution
    options = odeset('Events', @events);
    
    %The loop which connects the intervals of time
    for n = 1 : number_of_intervals
        
        for particle_num = 1:num_of_particles
    %===========================================
    [t_sol, y_sol] = ode45(@pm1dwoc, [tstart, tstop], w0{particle_num}, options);
    %===========================================
    %The number of steps within each interval
    n_steps = length(t_sol);
    
    for interval = 2: n_steps
            times{particle_num} = [times{particle_num}; t_sol(interval)];
            sols{particle_num} = [sols{particle_num}; y_sol(interval, :)];
    end

    %Setting the initial conditions of the next interval

    w0{particle_num} = y_sol(n_steps,:);

    y_adj(particle_num) = y_sol(n_steps, 1);

    x_adj(particle_num) = y_sol(n_steps, 3);
     
        end
    
    tstart = tstart + time_interval*1e-6;
    tstop = tstart + time_interval*1e-6;
    
    for n = 1:num_of_particles
    y_adj_stable(n) = y_adj(n);
    x_adj_stable(n) = x_adj(n);
    end
    end
%===============================================
 function dwdt = pm1dwoc (t,w)
        y=w(1);
        vy=w(2);
        x=w(3);
        vx=w(4);
        
        for particle_number = 1:num_of_particles
        Dist(particle_number) = sqrt((x - x_adj_stable(particle_number))^2 + (y - y_adj_stable(particle_number))^2);
        
        if (Dist(particle_number) > 0)
            x_vect(particle_number) = (x - x_adj_stable(particle_number))/Dist(particle_number);
            y_vect(particle_number) = (y - y_adj_stable(particle_number))/Dist(particle_number);
        end
        end
        
            
         dy_component = -qw*Vd/(m*G) + qw*(-qw)/(m*4*pi*epsilon0*(2*R+2*y)^2));
         dx_component = 0;
         for particle_number = 1:num_of_particles
             if (Dist(particle_number) > 0)
                dx_component = dx_component + ((qw^2)/(0.0001*m*4*pi*epsilon0*Dist(particle_number)^2))*x_vect(particle_number);
                dy_component = dy_component + ((qw^2)/(0.0001*m*4*pi*epsilon0*Dist(particle_number)^2))*y_vect(particle_number);
             end
         end
         
         dwdt = [vy; dy_component; vx; dx_component];
         
    end

    function [eventvalue,stopthecalc,eventdirection] = events (t,w)
        t= t*1e6;
        end_time = 10000;
        
        eventvalue = t - end_time/number_of_intervals;
        stopthecalc = 1;
        eventdirection = 1;
        
        for num = 2:number_of_intervals
            eventvalue = [eventvalue; t - num*(end_time/number_of_intervals)];
            stopthecalc = [stopthecalc; 1];
            eventdirection = [eventdirection; 1];
        end
        
    end
 
end

Any help would be really appreciated!

Thank You

Sam