Thank you Grzegorz Knor

I need more help in this topic. your suggestion I has been already try but it's not sufficient for my work.

You can for example add random number to your equation:

ode45(@(t,y)y+randn(),[0,1],1)

But can you explain your problem in more details?

Thank you Grzegorz Knor

I need more help in this topic. your suggestion I has been already try but it's not sufficient for my work.

It is hard to help if I don't know details :) It depends on how the noise is added to the model.

My another idea is to add noise function:

n = randn(100,1);

t = linspace(0,1,100);

p = spline(n,t);

ode45(@(t,y)ppval(p,t),t,1)

But realy it has no sense to answer without description of your problem.