How to run ode15s function for several times

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Thanks for taking the time to read this, I am new to matlab. The following four equations are what I need to solve them by ode15s:
eq1=diff(uc(t),2)==(-1/(L*(3*mc+4*h2*L*pi*a2*Ro)))*(3*(-Ft*L+4*h2*pi*a11*a2*(uc(t)+Beta*diff(uc(t)))+L*(alfa*mc*diff(uc(t))+pi*(p2(t)*a2^(2)-p1(t)*a2^(2)+2*h2*a12*(wr1(t)-wr2(t)+Beta*diff(wr1(t))-Beta*diff(wr2(t))))))+4*pi*h2*L^(2)*a2*alfa*Ro*diff(uc(t)));
eq2=(h2*L*a2^(2)*Ro)*diff(wr1(t),2)==(-h2*a12*a2*(uc(t)+Beta*diff(uc(t)))+L*(a2^(2)*p1(t)-h2*a22*(wr1(t)+Beta*diff(wr1(t))))-h2*L*a2^(2)*alfa*Ro*diff(wr1(t)));
eq3=(h2*L*a2^(2)*Ro)*diff(wr2(t),2)==(h2*a12*a2*(uc(t)+Beta*diff(uc(t))+L*(a2^(2)*p2(t)-h2*a22*(wr2(t)+Beta*diff(wr2(t)))))-h2*L*a2^(2)*alfa*Ro*diff(wr2(t)));
eq4=(pi*(L+uc(t))*(a1+wr1(t))^(2))*diff(p1(t))==(p1(t)-Bef)*((CD*Av*sqrt(2*(Bef-p1(t))*(p1(t)-p2(t))/(Bef*Rflu)))+pi*diff(uc(t))*(a2+wr1(t))^(2)+2*pi*(L+uc(t))*(a2+wr1(t))*diff(wr1(t)));
where uc,wr1,wr2,p1,p2 are state variables and mc,av Ft and t1 are fixed variables , all the other parameters are constant.
My problem is in the value of Ft=fo* sin(5000*t), for (t=0:0.63)sec then Ft=0 for (t=0.63:1)sec as a result for small increments I have 100 values of Ft and t1
I need to run my ode15s script 100 times for all 100 values of Ft and t1 then plot them in a single plot.
  2 个评论
Jan
Jan 2017-11-13
Okay. Then use loops to do this. Did you try this already? What exactly is the problem?
tamara hussien
tamara hussien 2017-11-13
编辑:Torsten 2017-11-13
Thank you Mr.Jan Simon for asking about my problem. The problem occurs when I'm making a loop as follow:
t=0
fo=10
w=5000
for i=1:1:100
if (t<=0.63e-3)
f=fo*sin(w*t);
else
f=0;
end
T(i)=t;
Ft(i)=f
t=t+0.00001
end
now when I call my function handle as
Q = @(t, y) f(t, y, Ft, Av, mc)
y0est = [0; 0; 0; 0; 0; 0; 0; 0]; % initial values y0=[uc,wr1,wr2,p1,p2,uc",wr1",wr2"]
yp0est = zeros(8,1);
opt = odeset('Mass', M, 'InitialSlope', yp0est,...
'RelTol', 10.0^(-6), 'AbsTol' , 10.0^(-6));
implicitDAE = @(t,y,yp) M(t,y)*yp - Q(t,y);
[y0, yp0] = decic(implicitDAE, 0, y0est, [], yp0est, [], opt);
opt = odeset(opt, 'InitialSlope', yp0);
t1=0:1e-4:1e-3;
t2=t1+1e-6;
[tSol,ySol] = ode15s(Q, [t1 t2], y0, opt)
% y is vector of all state variables, t is time, Ft,Av,and mc are fixed variables.
here I can solve it for only one value of Ft and t1 when I'm writing it as Q(i)= @(t, y) f(t, y, Ft(i), Av, mc) the matlab gives me the error as "Dimensions of matrices being concatenated are not consistent." If possible please give me your email address, then I will attach to you my matlab code, because it is to much i can't write it here. Best regards

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回答(1 个)

Yogananda Jeppu
Yogananda Jeppu 2017-11-13
Try a simple Euler integration. Xd = f(a,b,c ...). x = Xd*dt+x; store the values of x in an array. See if this works.
  2 个评论
tamara hussien
tamara hussien 2017-11-14
Thank you Mr Yogananda Jappu for your time. I already made a function handle for all variables but When I call back this fuction for n values of x as array, matlab returns to the error in the function handle” matrix dimensions must agree”
Steven Lord
Steven Lord 2017-11-14
tamara hussien had flagged this answer as "Good idea".
The purpose of flagging in the MATLAB Answers help is:
"A flag is a request for review that any contributor can assign to content. Contributors with sufficient privileges can then review and potentially revise, close, or delete the flagged content.
Questions, answers, and comments can be flagged if unclear, not appropriate, or spam."
Since you seem happy with the suggestion, I'm going to remove the flag.

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