In below mentioned codes, i wrote compliance (S) matrice and inverse this matrix to get the stiffnes matrice(Q). I write all of this code with a variable theta 'th'.
Now i want to plot vxy which is having relation with one of the element of matrice(Q), when i called the element S(1:2) it is showing two element. So matrice dimention are not satifying for plot. Also some problem with Gxy.
syms th
E1=181*10^9;
E2=10.30*10^9;
v12=0.28;
G12=7.17*10^9;
s11=1/E1;
s21=-v12/E1;
s13=0;
s12=s21;
s22=1/E2;
s23=0;
s66=1/G12;
s=[s11 s12 s13;s21 s22 s23;0 0 s66]; %s is compliance matrix in priciple coordinate
q=inv(s); %q is stiffness matrix in priciple coordinate
T=[cosd(th).^2, sind(th).^2, 2*sind(th)*cosd(th); sind(th).^2, cosd(th).^2, -2*sind(th)*cosd(th);-sind(th)*cosd(th), sind(th)*cosd(th), cosd(th).^2-sind(th).^2];
R=[1 0 0;0 1 0;0 0 2];
Q=inv(T)*q*R*T*inv(R) %Q is stiffness matrix in other then fiber coordinate
S=inv(Q) %S is compliance matrix in other then fiber coordinate
Ex=(1./(S(1:1)));
Ey=(1./(S(2:2)));
vxy=-Ex.*S(2:1)
vyx=-Ey.*S(1:2)
Gxy(th)=(1./(S(3:3)))
th=-90:1:90;
% Ex1 =vpa(Ex(th));
% plot(th,Ex1,'r')
%
% Ey1=vpa(Ey(th));
% plot(th,Ey1,'g')
vyx1=vpa(vyx(th))
plot(th,vyx1,'b')