matrices
How to add label to index the rows and columns of the matrix ?
because I want to number the line outside the matrix
\[
\begin{array}{lc}
\ Mat_{\varPhi to M} & \left(\begin{array}{@{}ccccc@{}}
1 & 1 & 1 & 1 & 1 \\
0 & 1 & 0 & 0 & 1 \\
0 & 0 & 1 & 0 & 1 \\
0 & 0 & 0 & 1 & 1 \\
0 & 0 & 0 & 0 & 1
\end{array}\right) \\[15pt]
\end{array}
\]
Here is one option using \bordermatrix that provides what you're after:
\documentclass{article}
\usepackage{mathtools}
\begin{document}
\[
\phantom{(17') \rightarrow\hspace{\arraycolsep}}% For correct horizontal spacing within display math \[ ... \]
\underbrace{
\bordermatrix{\hspace{-\arraycolsep} &
\overbrace{\hphantom{\dfrac{1-s_R}{\delta}}}^{x} &
\overbrace{\hphantom{- \dfrac{\frac{\lambda-1}{\lambda}}{\rho + \frac{n}{\eta} - n}}}^{c} \cr
\hspace{-\arraycolsep}\mathllap{(17') \rightarrow} & \dfrac{n}{\eta \cdot \delta} & \dfrac{1}{\lambda} \cr
\hspace{-\arraycolsep}\mathllap{(16') \rightarrow} & \dfrac{1-s_R}{\delta} & - \dfrac{\frac{\lambda-1}{\lambda}}{\rho + \frac{n}{\eta} - n}
}
}_{\text{coefficient matrix $\Delta$}}
\cdot
\begin{pmatrix}
\widetilde{x} \\
\widetilde{c}
\end{pmatrix} =
\begin{pmatrix}
1 \\ 0
\end{pmatrix}
\]
\end{document}
\overbraces are stretched to the widest element in each column using \hphantom, while care is taken to remove the left-most row indices from the \underbrace yet restoring their horizontal space outside of the \bordermatrix construction.
For having left braces to identify/mark the rows, you could use the following:
\[
\phantom{(17') \left\{\vphantom{\dfrac{n}{\eta \cdot \delta}}\right.\hspace{\dimexpr\arraycolsep-\nulldelimiterspace}}% For correct horizontal spacing within display math \[ ... \]
\underbrace{
\bordermatrix{\hspace{-\arraycolsep} &
\overbrace{\hphantom{\dfrac{1-s_R}{\delta}}}^{x} &
\overbrace{\hphantom{- \dfrac{\frac{\lambda-1}{\lambda}}{\rho + \frac{n}{\eta} - n}}}^{c} \cr
\hspace{-\arraycolsep}\mathllap{(17') \left\{\vphantom{\dfrac{n}{\eta \cdot \delta}}\right.\kern-\nulldelimiterspace} &
\dfrac{n}{\eta \cdot \delta} & \dfrac{1}{\lambda} \cr
\hspace{-\arraycolsep}\mathllap{(16') \left\{\vphantom{- \dfrac{\frac{\lambda-1}{\lambda}}{\rho + \frac{n}{\eta} - n}}\right.\kern-\nulldelimiterspace} &
\dfrac{1-s_R}{\delta} & - \dfrac{\frac{\lambda-1}{\lambda}}{\rho + \frac{n}{\eta} - n}
}
}_{\text{coefficient matrix $\Delta$}}
\cdot
\begin{pmatrix}
\widetilde{x} \\
\widetilde{c}
\end{pmatrix} =
\begin{pmatrix}
1 \\ 0
\end{pmatrix}
\]
Best Answer
Here is an option using
kbordermatrix:For more options and styles, including the usage of
\bordermatrix, see Where is the\matrixcommand?