# General matrices

I want to use LaTeX to add matrix that looks like this:

-----L_1-----

-----L_2-----

. . . . . . .

----L_n-----


and matrices where I want to show how a general cell in the matrix looks like (for example writing a matrix and then marking that 3 belongs to the i'th row and j'th column) , like here : (I am not looking to a way to add the vertical lines ,but I want to have a matrix filled with dots, except at the i,j place and there write $2^{i+j}$ [ I want a matrix that each cell has the value of 2^{row number +column number})

• Welcome to TeX.SX! I'm pretty sure there's already something like this on the site. – egreg Feb 18 '15 at 22:54
• Thanks :) I am pretty new here , and I didn't know how to explain what I need ... can you help me find this? – UserB95 Feb 18 '15 at 22:55
• Perhaps tex.stackexchange.com/questions/57411/… is what you want for the first problem – egreg Feb 18 '15 at 23:00
• And tex.stackexchange.com/questions/196258/… for the second problem. – egreg Feb 18 '15 at 23:02
• @egreg for the first question : can I add dots( I want to say that the matrix has n rows) For the second question : It is not exactly what I meant , I wanted to have a matrix , filled with dots, except at the i,j place and there write $2^{i+j}$ [ I want a matrix that each cell has the value of 2^{row number +column number} – UserB95 Feb 18 '15 at 23:15

For the first problem, look at Long dashes for denoting omitted columns of a matrix

For the second problem, the result will not be pretty:

\documentclass{article}
\usepackage{amsmath}

\begin{document}

$\begin{pmatrix} \makebox[9em]{\dotfill} \\ \makebox[9em]{\dotfill} \\ \makebox[9em]{\dotfill\ 2^{i+j} \dotfill} \\ \makebox[9em]{\dotfill} \\ \makebox[9em]{\dotfill} \\ \end{pmatrix}$

\end{document}


I'd very much prefer a simpler description:

The matrix $A=(a_{ij})$ where $a_{ij}=2^{i+j}$, for $1\le i,j\le n$ 