Accessing huge matrix of symfun?

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Ali Almakhmari 2023-7-27

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https://ww2.mathworks.cn/matlabcentral/answers/2001257-accessing-huge-matrix-of-symfun

关闭： Ali Almakhmari 2023-8-18

H.mat

在 MATLAB Online 中打开

I have this H.mat file with an H variable that is of type symfun. Its supposed to be a matrix with symbolic variables:

syms s
H(s) = C/(s*eye(size(A))-A)

and matrices C and A also contian multiple and many other symbolic variables. But when I got H (which I attached in the .mat file here), I cannot see its contents from the workspace (I believe its because its too big and complicated). So how can I index/call or get access in any other way to whats inside H?

Note: A is 12 by 12 and C is 6 by 12.

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Ali Almakhmari 2023-7-27

编辑：Ali Almakhmari 2023-7-27

在 MATLAB Online 中打开

Sure! Here is my full code:

%The Symbolic Variables
syms ksm ksn ksl wsm wsn wsl Delsm Delsn Delsl DelT m Delgx Delgy Delgz dx
syms tilda_Xu ro tilda_Xv qo tilda_Xw tilda_Xp wo tilda_Xq vo tilda_Xr tilda_Yu tilda_Yv po tilda_Yw uo tilda_Yp tilda_Yq tilda_Yr tilda_Zu tilda_Zv tilda_Zw tilda_Zp tilda_Zq tilda_Zr tilda_Lu tilda_Lv tilda_Lw tilda_Lp tilda_Ixx tilda_Lq tilda_Lr tilda_Mu tilda_Mv tilda_Mw tilda_Iyy tilda_Mp tilda_Mq tilda_Mr tilda_Nu tilda_Nv tilda_Nw tilda_Np tilda_Nq tilda_Nr tilda_Izz
syms tilda_X_delm tilda_X_deln tilda_X_dell tilda_Y_delm tilda_Y_deln tilda_Y_dell tilda_Z_delm tilda_Z_deln tilda_Z_dell tilda_L_delm tilda_L_deln tilda_L_dell tilda_M_delm tilda_M_deln tilda_M_dell tilda_N_delm tilda_N_deln tilda_N_dell mu_sm mu_sn mu_sl
% Defining A Matrix
F =[tilda_Xu, (ro+tilda_Xv) (-qo+tilda_Xw) tilda_Xp (-wo+tilda_Xq) (vo+tilda_Xr); (-ro+tilda_Yu) tilda_Yv (po+tilda_Yw) (wo+tilda_Yp) tilda_Yq (-uo+tilda_Yr); (qo+tilda_Zu) (-po+tilda_Zv) tilda_Zw (-vo+tilda_Zp) (uo+tilda_Zq) tilda_Zr; tilda_Lu tilda_Lv tilda_Lw tilda_Lp (tilda_Ixx*ro + tilda_Lq) (tilda_Ixx*qo + tilda_Lr); tilda_Mu tilda_Mv tilda_Mw (tilda_Iyy*ro + tilda_Mp) tilda_Mq  (tilda_Iyy*po + tilda_Mr); tilda_Nu tilda_Nv tilda_Nw (tilda_Izz*qo + tilda_Np) (tilda_Izz*po + tilda_Nq) tilda_Nr];
G = [tilda_X_delm tilda_X_deln tilda_X_dell; tilda_Y_delm tilda_Y_deln tilda_Y_dell; tilda_Z_delm tilda_Z_deln tilda_Z_dell; tilda_L_delm tilda_L_deln tilda_L_dell; tilda_M_delm tilda_M_deln tilda_M_dell; tilda_N_delm tilda_N_deln tilda_N_dell];
A = [F, G, zeros(6,3);zeros(3,6),zeros(3,3),eye(3);zeros(3,6), [-wsm^2,0,0;0,-wsn^2,0;0,0,-wsl^2], [-2*mu_sm*wsm,0,0;0,-2*mu_sn*wsn,0;0,0,-2*mu_sl*wsl]]; %The A matrix
% Defining C Matrix
HH = [0,0,0,1,0,0;0,0,0,0,1,0;0,0,0,0,0,1;tilda_Xu,tilda_Xv,tilda_Xw,tilda_Xp,(tilda_Xq-2*qo*dx) (tilda_Xr-2*ro*dx); (tilda_Yu+tilda_Nu*dx) (tilda_Yv+tilda_Nv*dx) (tilda_Yw+tilda_Nw*dx) (tilda_Yp+(qo+tilda_Izz*qo+tilda_Np)*dx) (tilda_Yq+(po+tilda_Izz*po+tilda_Nq)*dx) (tilda_Yr+tilda_Nr*dx); (tilda_Zu-tilda_Mu*dx) (tilda_Zv-tilda_Mv*dx) (tilda_Zw-tilda_Mw*dx) (tilda_Zp+(ro-tilda_Iyy*ro-tilda_Mp)*dx) (tilda_Zq-tilda_Mq*dx) (tilda_Zr+(po-tilda_Iyy*po+tilda_Mr)*dx)];
J = [0 0 0; 0 0 0; 0 0 0; tilda_X_delm tilda_X_deln tilda_X_dell; (tilda_Y_delm+tilda_N_delm*dx) (tilda_Y_deln+tilda_N_deln*dx) (tilda_Y_dell+tilda_N_dell*dx); (tilda_Z_delm-tilda_M_delm*dx) (tilda_Z_deln-tilda_M_deln*dx) (tilda_Z_dell-tilda_M_dell*dx)];
C = [HH J zeros(6,3)]; %The C matrix
%Finding H
syms s
H(s) = C/(s*eye(size(A))-A)

Ali Almakhmari 2023-8-17

编辑：Ali Almakhmari 2023-8-17

Its a 1 by 1 symFcn but when you open it you will get a matrix with multiple symFcn equations. The issue is that I cannot index that H to extract a specific symFcn equation in the matrix. For example, having H, how can I extract the symFcn in the 1st row, 2nd column?

Mann Baidi 2023-8-18