- #1

sristi89

- 8

- 0

So I have to solve a ODE (for dy/dt = K*(y-s) ) numerically in Matlab.

This is how I set it up:

K = 1;

s = 20;

y0 = 100;

npoints = 50;

dt = 0.1;

y = zeros(npoints,1); % this initializes the vector y to being all zeros

t = zeros(npoints,1);

y(1) = y0; % the initial condition

t(1) = 0.0;

for step=1:npoints-1 % loop over the timesteps

y(step+1) = y(step) + dt*K*(y(step)-s);

t(step+1) = t(step) + dt;

end

plot(t,y,'r'); %plots the numerical solution in red

hold on; %keep the previously plotted lines

My problem is that I have to "reset" the initial condition if the value of V(step+1)>150 with the initial condition (100). Then I have to let the loop continue with the new value.

I tried a bunch of combinations of the if statement in the for loop, but I can't make it work.

Any help would be really appreciated. Thanks!