How to compare solution of ODE for each time step?
2 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
This is the code I'm using now.
opts = odeset('MaxStep', 1);
[T,Y] = ode45(@hw0,[0 100],[0.01 10], opts);
plot(T,Y)
And hw0 is,
function dy = hw0(t,y)
D=0.02;
um=0.2;
Ks=0.05;
X0=0.01;
S0=0.1;
Sf=10;
dy = zeros(2,1);
dy(1) = -D*y(1) + (um*y(1)*y(2))./(Ks+y(2));
dy(2) = Sf * D - D*y(2) - (um*y(1)*y(2))./(0.4*(Ks+y(2)));
what I want to do is compare the y(i,1) and y(i+1,1) then change the ODE condition when y(i,1)-y(i+1,1)<=0.0001*y(i,1)
(change D as D+0.02 value then start ODE from this point, repeat this process until X becomes 0)
what I've tried is below, sadly it doesn't work as I expected.
function dy = hw3(t,y)
D=0.02;
um=0.2;
Ks=0.05;
X0=0.01;
S0=0.1;
Sf=10;
dy = zeros(2,1);
dy(1) = -D*y(1) + (um*y(1)*y(2))./(Ks+y(2));
dy(2) = Sf * D - D*y(2) - (um*y(1)*y(2))./(0.4*(Ks+y(2)));
n=numel(y(:,1));
for i=1:n-1
if abs(y(i,1)-y(i+1,1))<=0.0001*y(i,1)
ix=i;
D=D+0.02;
break
end
end
Then I'm planning ODE recursion from t=ix, recusion stops when Y(1)=0; anyway for now, finding ix is the main problem.
what should I do to find ix?
0 Kommentare
Antworten (1)
darova
am 2 Aug. 2021
t0 = 1;
while contdition
[t,x] = ode45(f,[0 t0],x0);
t0 = t(end);
end
0 Kommentare
Siehe auch
Kategorien
Mehr zu Ordinary Differential Equations finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!