Drexel dragonThe Math ForumDonate to the Math Forum



Search All of the Math Forum:

Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.


Math Forum » Discussions » Software » comp.soft-sys.matlab

Topic: ODE where y' = f(t,y0,...,yn)
Replies: 2   Last Post: Jul 23, 2007 4:13 AM

Advanced Search

Back to Topic List Back to Topic List Jump to Tree View Jump to Tree View   Messages: [ Previous | Next ]
C�dric L

Posts: 2
Registered: 4/7/05
Re: ODE where y' = f(t,y0,...,yn)
Posted: Jul 23, 2007 4:13 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

Thanks for your answer but I've got Matlab R12.1 only and I can't find these functions on my version. Is it normal ?
What can I do ?


"Steven Lord" <slord@mathworks.com> wrote in message <f7o7lp$8pr$1@fred.mathworks.com>...
>
> "redcic" <cedric.louyot@gmail.com> wrote in message
> news:1184861292.880614.114670@w3g2000hsg.googlegroups.com...

> > Hi all,
> >
> > I'm currently trying to solve an ODE that looks like this :
> > y' = f(t,y0,...,yn)
> >
> > where yi is the state vector taken at step i.

>
> This is not an ODE. This is a delay-differential equation.
>

> > This requires more explanation: I want ode45 to compute the state
> > vector y at times that I choose (like I can do using tspan). However I
> > need to use the state vector y computed at all the previous time steps
> > I've choosen in order to calculate y' at the current time step.
> >
> > Is there any way I do that using ode45 ?

>
> Use the delay-differential equation solvers DDE23 or DDESD instead.
>
> http://www.mathworks.com/access/helpdesk/help/techdoc/index.html?/access/helpdesk/help/techdoc/ref/dde23.html
> http://www.mathworks.com/access/helpdesk/help/techdoc/index.html?/access/helpdesk/help/techdoc/ref/ddesd.html
>
> --
> Steve Lord
> slord@mathworks.com
>
>





Point your RSS reader here for a feed of the latest messages in this topic.

[Privacy Policy] [Terms of Use]

© Drexel University 1994-2014. All Rights Reserved.
The Math Forum is a research and educational enterprise of the Drexel University School of Education.