Thread Subject:

method of steps for DDEs

Hi,
I need help with implementing a delay differential equation in Matlab to plot its bifurcation diagram. I use method of steps, however, I couldn't find any example on the internet on how to implement the method in Matlab. Is there any website which provides good example? Thanks a lot in advance.

On 5/8/2012 11:18 AM, Sanaa wrote:
> Hi,
> I need help with implementing a delay differential equation in Matlab to

Matlab some some functions like

"Solve delay differential equations (DDEs) with constant delays"

http://www.mathworks.com/help/techdoc/ref/dde23.html

may be this can help.

Thanks a lot for help. I am having another question if you please; how to integrate a function within a loop?
for example I am having a system of two discrete maps

y(i+1)= r*x(i)*(1-x(i));
x(i+1)= x(i)+ int('y(i+1)',n*r,t) ;
where n, r and t are given.
I loop over n but I want the time t to be in the interval [n*r,(n+1)*r]
Any idea please?

On 5/8/2012 1:59 PM, Sanaa wrote:
> Thanks a lot for help. I am having another question if you please;
>how to integrate a function within a loop?
> for example I am having a system of two discrete maps
>
> y(i+1)= r*x(i)*(1-x(i));
> x(i+1)= x(i)+ int('y(i+1)',n*r,t) ;
> where n, r and t are given.
> I loop over n but I want the time t to be in the interval [n*r,(n+1)*r]
> Any idea please?

int works on a function of some independent variable
like y(t) and you integrate over some range of t.

I do not understand what int('y(i+1)',n*r,t) is
supposed to mean, sorry.

You seem to be mixing symbolic stuff, arrays of
numerical stuff. too complicated for me.

--Nasser