I find in pst-plot.pdf, pst-func.pdf document but there is no its tutorial. So I hope anyone help me to draw the plot of it.(its code :-)) ). Thanks.

Example:
y=(x-2)/(2x+1)

Can anyone draw it by Pstricks environment?

documentclass{article}





usepackage{pgfplots}







begin{document}



begin{center}

begin{tikzpicture}[scale=2]

begin{axis}[axis lines=middle]

addplot[smooth,domain=-4:-8/11,purple,very thick] {(x-2)/(2*x+1)};

addplot[smooth,domain=-2/7:4,purple,very thick] {(x-2)/(2*x+1)};

draw[blue] (axis cs:-0.5,-6)--(axis cs:-0.5,6)

(axis cs:-4,0.5)--(axis cs:4,0.5);

fill[red] (axis cs:-0.5,0.5) circle(1mm);

end{axis}

end{tikzpicture}

end{center}

end{document}

documentclass[pstricks,border=12pt]{standalone}

usepackage{pst-plot}



begin{document}

begin{pspicture}[algebraic](-6,-6)(6,6)

  psaxes{->}(0,0)(-5.5,-5.5)(5.5,5.5)[$x$,0][$y$,90]

  psline[linecolor=red,linewidth=0.2pt](-0.5,-5.5)(-0.5,5.5)

  psline[linecolor=red,linewidth=0.2pt](-5.5,0.5)(5.5,0.5)

  psplot[plotpoints=1001,linecolor=blue,linewidth=2pt,

      yMaxValue=5.25]{-5.5}{5}{(x-2)/(2*x+1)}

  psdots[linecolor=red](-0.5,0.5)(0,0)(0,-2)(1,0)(2,0) 

end{pspicture}

end{document}

A PSTricks answer for the PSTricks question.

documentclass[pstricks,border=12pt]{standalone}

usepackage{pst-plot}

deff{(x-2)/(2*x+1)}



begin{document}

begin{pspicture}[algebraic](-4,-4)(6,5.5)

    psaxes{->}(0,0)(-4,-4)(5.5,5)[$x$,0][$y$,90]

    psline[linestyle=dashed,linecolor=red](-0.5,-4)(-0.5,5)

    psline[linestyle=dashed,linecolor=red](-4,0.5)(5,0.5)

    psset{linecolor=blue,linewidth=2pt}

    psplot{-4}{-7 9 div}{f}

    psplot{-2 9 div}{5}{f}

end{pspicture}

end{document}

NOTE

Increasing plotpoints sometimes is not a wise method because it will increase the size of its output (either PDF or SVG).

More flexible solution

documentclass[pstricks,border=12pt]{standalone}

usepackage{pst-plot}

deff(#1){((#1-2)/(2*(#1)+1))}% y=f(x)

defg(#1){((2+#1)/(1-2*(#1)))}% y=g(x) in which g is the inverse of f.



pstVerb{/I2P {AlgParser cvx exec} def}% infix to postfix operator



begin{document}

begin{pspicture}[algebraic](-4,-4)(6,6)

    psaxes{->}(0,0)(-4,-4)(5.5,5.5)[$x$,0][$y$,90]

    psline[linestyle=dashed,linecolor=red](-0.5,-4)(-0.5,5)

    psline[linestyle=dashed,linecolor=red](-4,0.5)(5,0.5)

    psset{linecolor=blue,linewidth=2pt}

    psplot{-4}{g(5) I2P}{f(x)}

    psplot{g(-4) I2P}{5}{f(x)}

end{pspicture}

end{document}