//// Continuous time ANN 
 clear; clf; 
 nn = 500; dx=1/nn; C=0; 

//// ode function
function udot=rnn_ode(t,u)
// odefile for recurrent network
 tau_inv = 1.;      // inverse of membrane time constant
 r=ones(nn,1)./(1+exp(-u)); 
 sum1=w*r*dx;
 udot=tau_inv*(-u+sum1+I_ext);
endfunction

//// Training weight matrix
pat=floor(2*rand(nn,10))-0.5;
w=pat*pat'; w=w/w(1,1); w=100*(w-C);
//// Update with localised input 
 tall = []; rall = []; t=(0:10)';
 I_ext=pat(:,1)+0.5; I_ext(1:10)=1-I_ext(1:10);
 u=ode(zeros(nn,1)+0.0001,0,t,rnn_ode);
 r=1.*(u>0); tall=[tall;t]; rall=[rall,r];
//// Update without input 
 I_ext=zeros(nn,1); t=(10:20)';
 u=ode(u(:,size(u,2)),10,t,rnn_ode);
 r=1.*(u>0); tall=[tall;t]; rall=[rall,r];
//// Plotting results
 plot(tall,4*(rall'-0.5)*pat/nn)