# How to draw this picture : a phase portrait in LATEX

Please I need some help. How can I draw this picture on Latex ? Thank you in advance.

• Welcome! Can you show any attempts you've made so far? Which graphics package(s) do you use? – Paul Gessler Apr 2 '16 at 23:45
• I do not master latex , in fact I have only discovered it a few days ago. So my skills are limited. I use Package Tikz. – kamil Apr 3 '16 at 0:01

A solution with pstricks. For the auto-pst-pdf package to work, launch pdflatex with the --enable-write18 switch, under MiKTeX, shell-escape for TeX Live or CMacTeX:

\documentclass[11pt,,section]{article}
\usepackage{auto-pst-pdf}

\begin{document}

\begin{pspicture}
\psset{unit=3cm}
\psaxes[yAxis=false, labels=none, ticksize=2.5pt -2.5pt]{-}(0,0)(-1.4,0)(1.4, 0)
\uput[d](-1,0){$x₀$}\uput[d](1,0){$x₀$}
\uput[d](0,0){$O$}
\psset{ArrowInside=-v, veearrowangle=40, veearrowlength=6pt, veearrowlinewidth=0.8pt,}
\psline[ArrowInsidePos=0.45]{-}(-1,0)(0, 0)
\psline[ArrowInsidePos=0.6]{-}(0, 0)(1,0)
\end{pspicture}

\end{document}


• Thank you, but how can I launch pdflatex with the --enable-write18 switch under Miktek ? – kamil Apr 3 '16 at 13:45
• The way depends on your editor. Which do you use? – Bernard Apr 3 '16 at 20:10