Index in position 2 exceeds array bounds
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Could someone please tell me what should I put for D2q in odefcn?
syms p Dp D2p q Dq D2q x
r=0.06;
s=0.3;
m=0.01;
f=0.075;
vmax=5;
smax=3;
xf=90;
w=0.15;
l=0.01;
a0=0.001;
h=0.2;
alpha=1;
pi=0.5;
mk=5;
mum=0.6;
t=0.1;
tp=0.05;
k=0.3;
a=((q+x*Dq)*t+(2*Dq*x+(x^2)*D2q)*s*tp)/(k-(2*Dq*x+(x^2)*D2q)*(tp^2));
m1=(Dp/p)*x*(m+a*t-mum)+0.5*(x^2)*((s+a*tp)^2)*(D2p/p);
t11=((w+m-r-f+mum)*(sqrt(vmax*alpha*xf)))/((pi^2)*sqrt(mk));
ode = p-(((x*alpha)*(w+m1+mum-r-f)^2)/((pi^4)));
D2ynum = solve(ode==0,D2p);
D2ynum = D2ynum(2);
f1 = matlabFunction(D2ynum,"Vars",{x, [p Dp q Dq D2q]})
ode1=q-((((p*f/x)-mum*x*Dq+(m+a*t)*Dq*x+0.5*((s+a*tp)^2)*(2*x*Dq+(x^2)*D2q)-0.5*k*(a^2))/(r-(m+a*t))));
D2ynum1 = solve(ode1==0,D2q);
D2ynum1 = D2ynum1(1);
f2 = matlabFunction(D2ynum1,"Vars",{x, [p Dp q Dq]})
odefcn = @(x,y)[y(2);f1(x, [y(1) , y(2), y(3), y(4)]);y(4);f2(x, [y(1), y(2), y(3) ,y(4)])];
bcfcn = @(ya,yb)[ya(1);yb(1)-t11;ya(4);yb(3)-((f*t11-0.5*k*(a^2)/((r-(m+t*a)))))];
xmesh = linspace(0.001,xf,10);
solinit = bvpinit(xmesh, [0.001 0.001 0.001 0.001]);
sol = bvp4c(odefcn,bcfcn,solinit);
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More Answers (1)
Walter Roberson
on 10 Jul 2023
f1 = matlabFunction(D2ynum,"Vars",{x, [p Dp q Dq D2q]})
5 variables bunched together, so f1 is going to expect to be able to index up to 5 for the second parameter.
odefcn = @(x,y)[y(2);f1(x, [y(1) , y(2), y(3), y(4)]);y(4);f2(x, [y(1), y(2), y(3) ,y(4)])];
but there you are only passing 4 values to the second parameter of f1.
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