# A dot using \pstThreeDDot

I want to put a dot on the beginning of the red line. My code is:

\documentclass[a4paper,pstricks,11pt]{report}
\usepackage{amssymb}
\usepackage{latexsym}
\usepackage{amsmath}
\usepackage[usenames]{color}
\usepackage{pst-solides3d}
\usepackage{pst-3dplot}

\begin{document}
\begin{center}
\begin{pspicture}(-2,-3)(4,6.5)
\psset{unit=1.0cm,viewpoint=50 17 20 rtp2xyz,lightsrc=viewpoint,opacity=0.7,grid}
\axesIIID[showOrigin=false,linewidth=1.5pt,arrowinset=0,arrows=->,arrowscale=1.5,labelsep=15pt](0,0,0)(5,5,5)
\defFunction[algebraic]{line}(t){3*cos(t)}{3*sin(t)}{0}
\psSolid[object=courbe,range=0 1.570796327,linewidth=1.5pt,linecolor=red,
function=line,r=0,action=draw]
\pstThreeDDot[SphericalCoor,linecolor=red](3,0,0)
\end{pspicture}
\end{center}
\end{document}


What is wrong here?

pst-solides3d and pst-3dplot are incompatible! The first one is a central projection and the other one a parallel projection. Use
\psSolid[object=point,linecolor=red,args=3 0 0]

or rotate the 3d coordinate system also for pst-3dplot. viewpoint is not valid for pstThreeDDot
• pst-solides3d has only 3d arrows: \psSolid[object=vecteur, args=1 2 2] For 2d arrows set first two 3d nodes and then \psline{<->}(A)(B) – user2478 Nov 26 '18 at 12:22
• Ok. Just one last question: I’m also trying to plot vector fields in the plane, namely the vector field $F(x,y) = \frac{\sqrt{2}x}{\sqrt{x^2 + y^2}} \mathbf{i} + \frac{\sqrt{2}y}{\sqrt{x^2 + y^2}} \mathbf{j}$. I used \psVectorfield but I don’t know very well how this command works (the pst-plot-doc pdf manual does not tell much about it). I also know that tikz package is an alternative... – Carl Nov 26 '18 at 12:39
• \pstVectorfield is a simple 2d vector filed of a given z=f(x,y) and should be easy to use. – user2478 Nov 26 '18 at 12:48