divisione matrice

Salve a tutti,

sto scrivendo un articolo con il pacchetto ieeetran e dovrei mostrare la matrice che genera le simulazioni, cioè i grafici finali. La matrice è molto grande e vorrei spezzarla in tre parti, 4 colonne, a capo altre 4 colonne, a capo le ultime 3.

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\begin{equation}
M =
\begin{bmatrix*}[l]
1 &0 &0 &0 &0 &0 &0 &0 &0 &0 &0 &0 &0 \\
0 &1 &0 &0 &0 &0 &0 &0 &0 &0 &0 &0 &0 \\
-(2 M_r h + 2 j M_f)\dot{\psi} &- 2 M_f e \dot{\psi} – 2 M_f e\cos\epsilon\dot{\delta} &M_f + M_r &0 &0 &0 &0 &0 &0 &0 &0 &0 &0 \\
0 &0 &0 &M_f + M_r &M_f k &M_r h + M_f j & M_f e &0 &0 &0 &0 &0 &0 \\
i_{f_y}\dot{\theta}_f + (i_{r_y} + I \beta)\dot{\theta}_r & i_{f_y}\sin\epsilon\dot{\theta}_f &0 & M_f k &I_{r_z} + M_f k^2 + I_{f_z} \cos\epsilon^2 + I_{f_x}\sin\epsilon^2 &I_{f_z}\cos\epsilon\sin\epsilon – I_{f_x}\cos\epsilon\sin\epsilon – C_{rxz} + M_f jk &I_{f_z}\cos\epsilon + M_f e k &0 &0 &0 &0 &0 &0 \\
0&-i_{f_y}\cos\epsilon\dot{\theta}_f &0 &M_r h + M_f j &I_{f_z}\cos\epsilon\sin\epsilon – I_{f_x}\cos\epsilon\sin\epsilon – C_{rxz} + M_f jk &I_{r_x} + M_f j^2 + M_r h^2 + I_{f_x}\cos\epsilon^2 + I_{f_z}\sin\epsilon^2 &I_{f_z}\sin\epsilon + M_f ej &0 &0 &0 &0 &0 &0 \\
i_{f_y}\cos\epsilon\dot{\theta}_f &K &0 &M_f e &I_{f_z}\cos\epsilon + M_f ek &I_{f_z}\sin\epsilon + M_f ej &I_{f_z} + M_f e^2 &0 &0 &0 &0 &0 &0 \\
(i_{r_y} + I\beta)\dot{\psi} &0 &0 &0 &0 &0 &0 &i_{r_y} + I\beta^2 &0 &0 &0 &0 &0 \\
i_{f_y}\dot{\psi} – i_{f_y}\cos\epsilon\dot{\delta} & i_{f_y}\sin\epsilon\dot{\psi} – i_{f_y}\cos\epsilon\dot{\phi} &0 &0 &0 &0 &0 &0 &i_{f_y} &0 &0 &0 &0 \\
0 &0 &0 &0 &0 &0 &0 &0 &0 &1 &0 &0 &0 \\
0 &0 &0 &0 &0 &0 &0 &0 &0 &0 &1 &0 &0 \\
0 &0 &0 &0 &0 &0 &0 &0 &0 &0 &0 &1 &0 \\
0 &-C_{f_1} t_r/\sigma_{f_y} &0 &0 &0 &0 &0 &0 &0 &0 &0 &0 &1
\end{bmatrix*}
\end{equation}
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