Lesson 12: Making Block Matrices in LATEX
按列分块：
[AAb⋯An−1b] $$ \left[ \begin{array}{c|c|c|c} A & Ab & \cdots & A^{n-1}b \end{array} \right] $$左右分块：
⎡⎣⎢⎢⎢⎢⎢a11a21⋮an1a12a22an2⋯⋯⋱⋯a1na2n⋮annb1b2⋮bn⎤⎦⎥⎥⎥⎥⎥ $$ \left[ \begin{array}{cccc|c} a_{11}&a_{12}&\cdots&a_{1n}&b_1\\ a_{21}&a_{22}&\cdots&a_{2n}&b_2\\ \vdots&&\ddots&\vdots&\vdots\\ a_{n1}&a_{n2}&\cdots&a_{nn}&b_n\\ \end{array} \right] $$四个对角：
C=[ACBD] $$ C= \left[ \begin{array}{c|c} A& B \\ \hline C& D \end{array} \right] $$
