The graph for the ODE45 function does not work
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The ODE 45 fuction for the second order derivative does not work, because the plot keeps ocilating and i have done a second method and it does not ocilates. How can i fix it?
The equation i am trying to solve is :
second derivative of delta_h + (Kc/A) * first derivative of delta_h + (Kc/(A*t1)) * delta_h = 0 %with Kc, A and t1 being constants
with initial conditions:
first derivative of delta_h(0) = 2 , delta_h(0) =0
i have added the other code for comparison. In this code the same fuction reaches zero very quickly and without ocilations. I dont know why they are not similar.
HWIK on 16 Jan 2022
I think the script where you use ode45 is correct, because I don't see any errors there, and using a different method I get the same reult:
Kc = 1;
A = 2;
t1 = 0.1;
dh = diff(h);
ode = diff(h,t,2) + Kc/A*dh + Kc/A/t1*h == 0;
cond1 = h(0) == 0;
cond2 = dh(0) == 2;
conds = [cond1, cond2];
hSol(t) = dsolve(ode,conds);
Perhaps the mistake is in the coursework_2.m script, but I am not sure what method you are using there to solve the ODE, so can't really help with that.