\documentclass{article} \usepackage{pstricks} \usepackage{pst-3d} \parindent=0pt \pagestyle{empty} \begin{document} \begin{center} \begin{pspicture}(-0.5,-0.5)(4.25,4.25) \psgrid[subgriddiv=0,griddots=5,gridlabels=7pt] \psline{->}(4,0)\psline{->}(0,4) \psline[linewidth=3pt,linecolor=red](0,0.5)(3,4) \end{pspicture} \hspace{1cm} \begin{pspicture}(-0.5,-0.5)(4.25,4.25) \pstilt{45}{% \psgrid[subgriddiv=0,griddots=5,gridlabels=7pt] \psline{->}(4,0)\psline{->}(0,4) \psline[linewidth=3pt,linecolor=red](0,0.5)(3,4) } \psline[linewidth=0.5pt,linestyle=dashed](0,0)(0,4) \psarc{->}(0,0){2}{45}{90}\rput(0.5,1.5){\large$\alpha$} \end{pspicture} \end{center} \end{document}