Why am I getting error in event function for impulsive differential equations?

function  sol = paper_impulse
t0 = 0; t1 = 5; 
impcount = 0; te=1; k=1; No = 1; ep=0.01; vec = []; x = []; i=0; impulse_strength = 1.2;
v=zeros(201);
while(i<5)
    i = i+0.01;
    x = [x, i];
end
disp(x)
x= round(x*100)/100;
while true
         if (impcount ==0)
            options = odeset('Events',@events,'AbsTol',1e-5,'RelTol',1e-5);
            
            sol = ode45(@neural_network, [t0, t1], [3 5], options);
            
          else
            % Specify the new solution at impulse times...
            
            options = odeset(options,'InitialY',[impulse_strength*sol.y(1,end) impulse_strength*sol.y(2,end)]);
            sol = ode45(@neural_network, [t0, t1], sol, options);              
         end
         t0 = sol.x(end);
         fprintf('Restart at %5.2f.\n',t0);
         vec = [vec,te];
         ind = find(abs(x-te)<0.001);
         v(ind) = v(ind) + impulse_strength;
         fprintf('Restart at %5.2f.\n',ind);
         k=k+1;
         if(mod(k,No) == 0)
             te = te+ No*(0.02-ep)+ep;
         else
             te = te+ ep;
         end 
         
         impcount = impcount + 1;
        
         if (t0 >= t1)
            
            break;
         end
         
end
plot(sol.x, sol.y(1,:));
hold on
plot(sol.x, sol.y(2,:));
%disp(size(vec));
%stem(vec, v);
%axis([1 5 0 impulse_strength*2]);
%xlabel('time');
%ylabel('impulse strength');

function dy = neural_network(t,y)
  dy = zeros(2,1);
  
  dy(1) = -1/2*y(1)-y(1).^3+y(1).*y(2).^2-((y(1).^2+y(2).^2).^1/4).*sign(y(1));
  dy(2) = -1/2*y(2)-y(2).^3-y(2).*y(1).^2-((y(1).^2+y(2).^2).^1/4).*sign(y(2));
end
function [value,isterminal,direction] = events(t,y)
         value = t-te;
         isterminal = 1;
         direction  = 0;
end
 end
    

The above code is for impulsive differential equation. I have used the event function to locate the moments at which the solution has jump kind of discontinuites. But code is compiling with errors. Please help to short out this problem.

[Torsten]

From the code I see, "te" seems to be undefined when you first call ode45.

[Rakesh]

Thanks for your response. When I run this code then I am getting the following errors.

Error using odeset

Unrecognized property name 'InitialY'.

Error in paper_impulse (line 20)

options = odeset(options, 'InitialY', [impulse_strength*sol.y(1,end) impulse_strength*sol.y(2,end)]);

Answer 1

[Walter Roberson]

https://www.mathworks.com/help/matlab/ref/ddeset.html

InitialY is only for Delay Differential Equations using ddeset()

[Rakesh]

Thank for your answer. What can I use for odeset() in place of InitialY?

[Torsten]

If with "InitialY" you mean "initial values for Y": it is not specified in the options structure, but as the third argument in the call to ode45.