dear all
i have code like below :
clcclear allN=4;L=60e-3;M=3.338e-3;jx=5.743e-14;E=2.1e11;x = sym('x', [1 3*N], 'real');for j=2:N+1 for i=j-1 f1(j)=(1-cos(x(3*i-2)))/x(3*i-2); g1(j)=-(1-cos(x(3*i-1)))/x(3*i-1); f2(j)=sin(x(3*i-2))/x(3*i-2); g2(j)=sin(x(3*i-1))/x(3*i-1); pl(:,j)=L*[f1(j) f2(j)*g1(j) f2(j)*g2(j)]'; Rl(:,:,j)=[cos(x(3*i))*cos(x(3*i-2)) -sin(x(3*i))*cos(x(3*i-2)) sin(x(3*i-2));cos(x(3*i))*sin(x(3*i-2))*sin(x(3*i-1))+sin(x(3*i))*cos(x(3*i-1)) -sin(x(3*i))*sin(x(3*i-2))*sin(x(3*i-1))+cos(x(3*i))*cos(x(3*i-1)) -cos(x(3*i-2))*sin(x(3*i-1));-cos(x(3*i))*sin(x(3*i-2))*cos(x(3*i-1))+sin(x(3*i))*sin(x(3*i-1)) sin(x(3*i))*sin(x(3*i-2))*cos(x(3*i-1))+cos(x(3*i))*sin(x(3*i-1)) cos(x(3*i-2))*cos(x(3*i-1))]; p(:,2)=pl(:,2); endendR(:,:,2)=Rl(:,:,2);R(:,:,1)=[1 0 0;0 1 0;0 0 1];for i=3:N+1 R(:,:,i)=R(:,:,i-1)*Rl(:,:,i); p(:,i)=p(:,i-1)+R(:,:,i-1)*pl(:,i);endfor j=2:N+1 for i=1:N for r=1:N d1Pbeta(:,j,i)=diff(p(:,j),x(3*i-2)); d2Pbetabeta(:,j,i,r)=dot([-M*9.81 0 0],diff(d1Pbeta(:,j,i),x(3*r-2))); end endendfor i=1:N for r=1:N for j=2:N+1 sigm(i,r)=(E*jx/L)+sum(d2Pbetabeta(:,j,i,r)'); end endend
here i want to replace x with number
x=[0.0495837022782378;3.96268247549320e-09;-4.78044641555791e-10;0.0854433755724521;2.89430795211353e-09;-1.43061297211777e-10;0.110831068380515;4.80530147316531e-09;-5.69420213726607e-10;0.125761304817654;1.09464269988965e-08;-4.73181277688372e-10]
but it doesnt work
and after that calculate eigenvalue of sigm
e=eig(sigm)
Best Answer