# The diagonal line in the matrix

please tell me how you can draw this matrix?

• Welcome! What have you tried so far? Can you show us some code? Did you search this web page? I think that was allready answered ... – Kurt Apr 23 '16 at 22:18

A solution with pstricks:

\documentclass{article}
\usepackage{pst-node, pst-plot}
\usepackage{auto-pst-pdf}
\def\fput(#1)#2{\rput(#1){\psframebox*{$#2$}}}

\begin{document}

\begin{pspicture}(0,0)(8,6)
\psset{dy=-1, labels=none, ticks=none, xunit =0.8, yunit=-0.5, linejoin=1,arrowinset=0.15}
\psline{ <->}(0,10)(0,0)(11,0)
\pnodes{X}(0,0)(2,0)(4,0)(6,0)(8,0)(10,0)
\pnodes{Y}(0,0)(0,2)(0,4)(0,6)(0,8)(0,10)
\psset{nodesep=2pt}
\begin{psclip}{\psframe[linestyle=none, framesep=2pt](0,0)(6.5,6)}
\ncline{X1}{Y1}
\ncline{X2}{Y2}
\ncline{X3}{Y3}
\ncline{X4}{Y4}
\ncline{X5}{Y5}
\end{psclip}
\fput(1,1){a_1b_1}\fput(3,1){a_2b_1}\fput(5,1){a_3b_1}
\fput(1,3){a_1b_2}\fput(3,3){a_2b_2}\fput(5,3){a_3b_2}
\fput(1,5){a_1b_3}\fput(3,5){a_2b_3}\fput(5,5){a_3b_3}
\psset{linestyle =dotted, linewidth=1.5pt}
\psline(0.8,7)(10,7)
\begin{psclip}{\psframe[linestyle=none, framesep=2pt](6.4,0)(9.9,6)}
\multido{\i =1+2}{3}{\psline(6.3,\i)(10,\i)}
\end{psclip}
\end{pspicture}

\end{document}


• Bernard, thank you kindly, I have long worked this matrix, the problem was the diagonal line. – Иван Нода Apr 25 '16 at 22:42
• You're welcome. I'm glad to have been helpful! – Bernard Apr 25 '16 at 22:44