Added matlab code samples.

All of these code samples currently are mis-identified in my repositories. I'm
donating them to the cause.

samples/Matlab/RK4.m

@@ -0,0 +1,24 @@
+function x = RK4( fun, tspan, ci, mu )
+%RK4 4th-order Runge Kutta integrator
+%   Detailed explanation goes here
+h=1e-5;
+t=tspan(1);
+T=tspan(length(tspan));
+dim=length(ci);
+%x=zeros(l,dim);
+x(:,1)=ci;
+i=1;
+while t<T
+	k1=fun(t,x(:,i),mu);
+	k2=fun(t+h/2,x(:,i)+k1*h/2,mu);
+	k3=fun(t+h/2,x(:,i)+k2*h/2,mu);
+	k4=fun(t+h,x(:,i)+h*k3,mu);
+	x(:,i+1)=x(:,i)+(h/6*(k1+2*k2+2*k3+k4));
+	t=t+h;
+	i=i+1;
+end
+x=x';
+% 	function events(x)
+% 	dist=
+% 	return 
+end