清空筛选条件
清空筛选条件

Received this error, not sure how to fix

2 次查看（过去 30 天）
Anita Burns
Anita Burns 2024-4-23
回答： Walter Roberson 2024-4-23
Ran in:
**This code was copied from a textbook so I'm not sure why it does not work.
Index exceeds the number of array elements. Index must not exceed 6.
Error in HW6 (line 62)
wmax(i,j)=wmax(i,j)+(16*PO/(pi^6))*sin(pi*M(mi)*xc/a)*sin(pi*N(ni)*yc/b)/(M(mi)*N(ni)*(D11*(M(mi)/a)^4+2*(D12+2*D66)*(M(mi)/a)^2*(N(ni)/b)^2+D22*(N(ni)/b)^4));
Here is the code:
E1=38.6E9;
E2=8.27E9;
G12=4.14E9;
v12=0.26;
v21=E2*v12/E1;
theta=[0 90 90 0];
h=[-0.0025 -0.00125 0 0.00125 0.0025];
a=0.5;
b=0.25;
M=1:2:11;
N=1:2:11;
PO=10;
xc=a/2;
yc=b/2;
z=h(1);
x=0:0.01:xc;
D=zeros(3,3);
wmax=zeros(6,6);
WO=zeros(1,length(x));
epsilonX=zeros(1,length(x));
epsilonY=zeros(1,length(x));
epsilonXY=zeros(1,length(x));
for i=1:length(theta)
m=cosd(theta(i));
n=sind(theta(i));
Q11=E1/(1-v12*v21);
Q12=E2*v12/(1-v12*v21);
Q22=E2/(1-v12*v21);
Q66=G12;
T1=[m^2 n^2 2*m*n;n^2 m^2 -2*m*n;-m*n m*n m^2-n^2];
T2=[m^2 n^2 m*n;n^2 m^2 -m*n;-2*m*n 2*m*n m^2-n^2];
Q=[Q11 Q12 0;Q12 Q22 0;0 0 Q66];
QBAR(:,:,i)=inv(T1)*Q*T2;
Di(:,:,i)=(1/3)*(h(i+1)^3-h(i)^3)*QBAR(:,:,i);
end
for j=1:length(theta)
D=Di(:,:,j)+D;
end
D11=D(1,1);
D12=D(1,2);
D22=D(2,2);
D66=D(3,3);
for i=1:length(M)
for j=1:length(N)
for mi=1:i
for ni=1+j
wmax(i,j)=wmax(i,j)+(16*PO/(pi^6))*sin(pi*M(mi)*xc/a)*sin(pi*N(ni)*yc/b)/(M(mi)*N(ni)*(D11*(M(mi)/a)^4+2*(D12+2*D66)*(M(mi)/a)^2*(N(ni)/b)^2+D22*(N(ni)/b)^4));
end
end
end
end
Index exceeds the number of array elements. Index must not exceed 6.
QBARTOP=QBAR(:,:,1);
for i=1:length(x)
for mi=1:length(M)
for ni=1:length(N)
WO(i)=WO(i)+(16*PO/(pi^6))*sin(pi*M(mi)*x(i)/a)*sin(pi*N(ni)*yc/b)/(M(mi)*N(ni)*(D11*(M(mi)/a)^4+2*(D12+2*D66)*(M(mi)/a)^2*(N(ni)/b)^2+D22*(N(ni)/b)^4));
epsilonX(i)=epsilonX(i)-z*(-(16*PO/(pi^6))*(pi*M(mi)/a)^2*sin(pi*M(mi)*x(i)/a)*sin(pi*N(ni)*yc/b)/(M(mi)*N(ni)*(D11*(M(mi)/a)^4+2*(D12+2*D66)*(M(mi)/a)^2*(N(ni)/b)^2+D22*(N(ni)/b)^4)));
epsilonY(i)=epsilonY(i)-z*(-(16*PO/(pi^6))*(pi*N(ni)/b)^2*sin(pi*M(mi)*x(i)/a)*sin(pi*N(ni)*yc/b)/(M(mi)*N(ni)*(D11*(M(mi)/a)^4+2*(D12+2*D66)*(M(mi)/a)^2*(N(ni)/b)^2+D22*(N(ni)/b)^4)));
epsilonXY(i)=epsilonXY(i)-2*z*((16*PO/(pi^6))*(pi*N(ni)/b)*(pi*M(mi)/a)*cos(pi*M(mi)*x(i)/a)*cos(pi*N(ni)*yc/b)/M(mi)*N(ni)*(D11*(M(mi)/a)^4+2*(D12+2*D66)*(M(mi)/a)^2*(N(ni)/b)^2+D22*(N(ni)/b)^4));
deltaX(i)=QBARTOP(1,1)*epsilonX(i)+QBARTOP(1,2)*epsilonY(i)+QBARTOP(1,3)*epsilonXY(i);
deltaY(i)=QBARTOP(1,2)*epsilonX(i)+QBARTOP(2,2)*epsilonY(i)+QBARTOP(2,3)*epsilonXY(i);
end
end
end
subplot(2,1,1);
plot(x,WO, 'r.-'); grid on;
xlabel('Distance from edge x, m');
ylabel('Deflection wo, m');
subplot(2,1,2);
plot(x,abs(deltaX), 'g-*') ; grid on; hold on;
plot(x,abs(deltaY),'k-o');
xlabel('Distance from edge x, m');
ylabel("Bending stress, N/m^2");

请先登录，再回答此问题。

采纳的回答

Torsten
Torsten 2024-4-23
编辑：Torsten 2024-4-23
Maybe you mean
for ni=1:j
instead of
for ni=1+j
If not, you try to access N(7) which does not exist.
  1 个评论
Anita Burns
Anita Burns 2024-4-23
Thank you!! I have looked over this so many times and not caught that. I feel silly.

请先登录，再进行评论。

更多回答（1 个）

Walter Roberson
Walter Roberson 2024-4-23
M=1:2:11;
N=1:2:11;
those are length 6
for i=1:length(M)
for j=1:length(N)
for mi=1:i
for ni=1+j
when j becomes length(N) then ni becomes 1+length(N)
wmax(i,j)=wmax(i,j)+(16*PO/(pi^6))*sin(pi*M(mi)*xc/a)*sin(pi*N(ni)*yc/b)/(M(mi)*N(ni)*(D11*(M(mi)/a)^4+2*(D12+2*D66)*(M(mi)/a)^2*(N(ni)/b)^2+D22*(N(ni)/b)^4));
You index N(ni) when ni is potentially 1+length(N) . So you are indexing N(1+length(N)) which is going to be out of range.

类别

在 Help Center 和 File Exchange 中查找有关 Matrix Indexing 的更多信息

标签

产品


版本

R2023a

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by