<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Yesterday, among my posts was one which was perhaps too complicated, <div>involving trying to draw a surface and a curve on the surface. </div><div>Since no one has responded, I have tried to</div><div>separate some of these issues, and at the moment have two simple (I hope) questions:</div><div><br></div><div>******************************************************************************************************</div><div>1. The following code produces the attached picture which follows; if I uncomment the commented stuff</div><div>(except the first line, thereby trying to draw the same picture using fusion), </div><div>I get the error message shown below the picture.</div><div><br></div><div><blockquote type="cite"><div><font class="Apple-style-span" color="#000000">% !TEX TS-program = latex</font></div><div><font class="Apple-style-span" color="#000000">\listfiles</font></div><div><font class="Apple-style-span" color="#000000">\documentclass[11pt]{article}</font></div><div><font class="Apple-style-span" color="#000000">\usepackage{pst-solides3d, pst-3dplot, pst-math,pstricks-add}</font></div><div><font class="Apple-style-span" color="#000000">\usepackage{pst-3d}</font></div><div><font class="Apple-style-span" color="#000000">\begin{document}</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">\begin{pspicture}(-0.5,-2)(3,3)</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">\psset{solidmemory}</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">\psset{lightsrc=50 20 50, viewpoint=15 60 70 rtp2xyz,</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">Decran=50}</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">\psSurface[</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000"> fillcolor=gray,</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000"> incolor=green,</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000"> ngrid=0.1 0.1,</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000"> algebraic,</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000"> grid,% comment it out to see meaning of ngrid</font></div><div><font class="Apple-style-span" color="#000000">%</font><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">action=none,</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">name=graphsurf,</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">](-1,-1)(1,1){ (x^2-3*y^2)/2 }</font></div><div><font class="Apple-style-span" color="#000000">%%</font><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">\psSolid[</font></div><div><font class="Apple-style-span" color="#000000">%%</font><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">object=fusion,</font></div><div><font class="Apple-style-span" color="#000000">%%</font><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">action=draw**,</font></div><div><font class="Apple-style-span" color="#000000">%%</font><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">base=graphsurf,</font></div><div><font class="Apple-style-span" color="#000000">%%</font><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">]</font></div><div><font class="Apple-style-span" color="#000000">%%</font><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">\composeSolid</font></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span></div><div><span class="Apple-tab-span" style="white-space:pre"><font class="Apple-style-span" color="#000000"> </font></span><font class="Apple-style-span" color="#000000">\end{pspicture}</font></div><div><font class="Apple-style-span" color="#000000">\end{document}</font></div></blockquote>++++++++++++++++++++++++++++++++++++++++++</div><div></div></body></html>