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Index in position 2 exceeds array bounds

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Della
Della 2023-7-10
评论： Della 2023-7-10
Ran in:
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]})
f1 = function_handle with value:
@(x,in2)in2(:,1).*1.0./x.^2.*1.0./((in2(:,3)./1.0e+1+in2(:,4).*x.*(1.3e+1./1.0e+2)+in2(:,5).*x.^2.*(3.0./2.0e+2))./((in2(:,4).*x)./1.0e+1+(in2(:,5).*x.^2)./2.0e+1-6.0)-3.0./1.0e+1).^2.*((sqrt(in2(:,1)).*1.0./sqrt(x))./4.0-(in2(:,2).*x.*((in2(:,3)./1.0e+1+in2(:,4).*x.*(1.3e+1./1.0e+2)+in2(:,5).*x.^2.*(3.0./2.0e+2))./((in2(:,4).*x)./2.0e+1+(in2(:,5).*x.^2)./4.0e+1-3.0)+5.9e+1./1.0e+2))./in2(:,1)+1.23e+2./2.0e+2).*-2.0
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);
Warning: Solutions are only valid under certain conditions. To include parameters and conditions in the solution, specify the 'ReturnConditions' value as 'true'.
D2ynum1 = D2ynum1(1);
f2 = matlabFunction(D2ynum1,"Vars",{x, [p Dp q Dq]})
f2 = function_handle with value:
@(x,in2)-(1.0./x.^2.*(in2(:,1).*1.8e+3-in2(:,3).*x.*1.2e+3-in2(:,4).*x.^2.*1.2e+4+in2(:,3).^2.*x.*4.0e+2+in2(:,4).^2.*x.^3.*8.76e+2-in2(:,4).*in2(:,1).*x.*3.0e+1+in2(:,4).*in2(:,3).*x.^2.*1.06e+3))./(in2(:,1).*-1.5e+1+x.*1.08e+3+in2(:,3).*x.*1.3e+2+in2(:,4).*x.^2.*2.38e+2)
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);
Index in position 2 exceeds array bounds. Index must not exceed 4.

Error in symengine>@(x,in2)in2(:,1).*1.0./x.^2.*1.0./((in2(:,3)./1.0e+1+in2(:,4).*x.*(1.3e+1./1.0e+2)+in2(:,5).*x.^2.*(3.0./2.0e+2))./((in2(:,4).*x)./1.0e+1+(in2(:,5).*x.^2)./2.0e+1-6.0)-3.0./1.0e+1).^2.*((sqrt(in2(:,1)).*1.0./sqrt(x))./4.0-(in2(:,2).*x.*((in2(:,3)./1.0e+1+in2(:,4).*x.*(1.3e+1./1.0e+2)+in2(:,5).*x.^2.*(3.0./2.0e+2))./((in2(:,4).*x)./2.0e+1+(in2(:,5).*x.^2)./4.0e+1-3.0)+5.9e+1./1.0e+2))./in2(:,1)+1.23e+2./2.0e+2).*-2.0

Error in solution>@(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)])] (line 31)
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)])];

Error in bvparguments (line 105)
testODE = ode(x1,y1,odeExtras{:});

Error in bvp4c (line 122)
bvparguments(solver_name,ode,bc,solinit,options,varargin);

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采纳的回答

Torsten
Torsten 2023-7-10
移动：Torsten 2023-7-10
I already showed you how to solve "ode" as well as "ode1" simultaneously for D2p and D2q. This is necessary because both depend on D2q.

更多回答（1 个）

Walter Roberson
Walter Roberson 2023-7-10
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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