Sanaa
Posts:
171
Registered:
3/20/12


Re: Integration with variable limits
Posted:
Aug 16, 2013 9:59 AM


"Torsten" wrote in message <kul93r$t5q$1@newscl01ah.mathworks.com>... > "Sanaa" wrote in message <kul7kv$a10$1@newscl01ah.mathworks.com>... > > > > > > y_(n+1)=x_n; > > > > x_(n+1)= x_n + integration (f(y_(n+1)(s))) ds. > > > > > > So your final aim is to solve the delay differential equation > > > dx(t)/dt = rho*x(tr)*(1x(tr)) > > > with x given on an interval of length r at the beginning, r and rho constant over time ? > > > > > > Best wishes > > > Torsten. > > > > No. I don't want to solve the original delay differential equations, I wish to solve the discrete system after a certain discretization method applied to it. > > Thanks a lot in advance. > > But if the discretrization method is given, you are also given how the above integral is approximated. > Or are you _searching_ for an adequate discretization method for the delay differential equation ? > > Best wishes > Torsten.
Thanks once again for your kind reply. The discretization method here is very simple, the step methods, I am not searching for the method, i just don't know how to approximate the integral. I have read about trapz and cumtrapz but my only problem now is the variable limits of integration. Using trapz or cumptrapz don't allow me to specify the variable limits; I am really confused.

