ODE45 change y at event
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Can i influence the 'y' during an ode45 at a certain event?
I want to let the ODE45 stop at a certain event, manipulate the result at that timepoint and let it run further using the manipulated result as initial condition.A basic example is this:
spawnday=250;
function [value,isterminal,direction] = half_y_at_event(t, y, spawnday)
value = [t-spawnday];
isterminal = [1];
direction = [];
end
options=odeset('Events', @half_y_at_event, 'AbsTol', 1e-8, 'RelTol', 1e-8);
[t1, y1, te, ye, ie] = ode45(@dget_y, [0 500], [y_0], options, [pars]);
ye=ye/2;
[t2, y2] = ode45(@dget_y, [0 500], [ye], options, [pars]);
Is there a possibility to combine both ODE45 into one?
Mergin the matrices later is not an option.
2 个评论
darova
2019-10-4
Using ode45 two times?
[t1, y1, te, ye, ie] = ode45(@dget_y, [0 500], [y_0], options, [pars]);
ye = ye/2;
[t2, y2] = ode45(@dget_y, [0 500]+t1(end), ye(:,end));
采纳的回答
Steven Lord
2019-10-14
You can use the ballode example as a model. That has an events function that stops the solver each time the bouncing ball touches the ground. It then changes the initial condition (based on the solution the solver gave when the event occurred) and starts the solver again with the new initial condition.
edit ballode
3 个评论
Corentin Dewez-Raszka
2020-9-24
编辑:Corentin Dewez-Raszka
2020-9-24
Hey, sorry to disturb, but I have the ame problem you did, where can I get the code for ballode ?
EDIT : nevermind, found it, thx guys
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