问题
latex 编辑公式时需要合并行与列
实例
使用 \multirow 和 \multicolumn
% \footnotesize
\small
\begin{equation}
\Delta l_p = \left
\{
\setlength\arraycolsep{2pt}
\begin{array}{lll}
A , & F, & \multirow[t]{2}{1cm}{$ \mathrm{for~} k = 3,6,7, $} \\
B, & G, & \\
C , & H, & \multirow[t]{2}{1cm}{$ \mathrm{for~} k = 2,10,8, $} \\
D, & I, & \\
E, & \multicolumn{2}{c}{\mathrm{for~} k=10, 4,}
\end{array}
\right.
\label{Eq::Length}
\end{equation}
\normalsize
参考
The multirow, bigstrut and bigdelim packages
Vertical Alignment in multirow using cells with >1 lines
