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<p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; "><br class="Apple-interchange-newline">Zbigniew Nitecki</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Department of Mathematics</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Tufts University</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Medford, MA 02155</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; font-size: 12px; "><br></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">telephones:</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Office<span class="Apple-converted-space"><span class="Apple-converted-tab"> <span class="Apple-converted-space"> </span></span></span>(617)627-3843</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Dept.<span class="Apple-converted-space"><span class="Apple-converted-tab"> <span class="Apple-converted-space"> </span></span></span>(617)627-3234</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font-size: 12px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Dept. fax<span class="Apple-converted-space"><span class="Apple-converted-tab"> <span class="Apple-converted-space"> </span></span></span>(617)627-3966</font></p><span class="Apple-style-span" style="font-size: 12px; "><a href="http://www.tufts.edu/~znitecki/">http://www.tufts.edu/~znitecki/</a></span>
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<br><div><div>On Sep 9, 2010, at 5:30, Herbert Voss wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div><br>Here is what I get, when using the following code:<br><br>\documentclass{article}<br><br>\usepackage{pst-solides3d,pst-plot,amsmath}<br>\def\abs#1{\vert#1\vert}<br>\newcommand\zslicepos{%<br> \pspolygon[fillstyle=solid, fillcolor=gray!40, linestyle=none]%<br> (-2,-2)(2,-2)(2,2)(-2,2)<br> \psline[linestyle=dashed]{<->}(-2.5,0)(2.5,0)\uput[r](2.5,0){$x$}<br> \psline[linestyle=dashed]{<->}(0,-2.5)(0,2.5)\uput[u](0,2.5,0){$y$}<br> \psline[linecolor=darkgray](-2,-2)(2,2)<br> \psline[linecolor=darkgray](-2,2)(2,-2)<br> \parametricplot [linewidth=1.2pt]{-1.73}{1.73}{1 t dup mul add 0.5 exp t}<br> \parametricplot [linewidth=1.2pt]{-1.73}{1.73}{1 t dup mul add 0.5 exp<br>neg t}<br> \uput[d](0,-2.5){$z=c>0: x^{2}-y^{2}=c$}}<br>\newcommand\zsliceneg{%<br> \pspolygon[fillstyle=solid, fillcolor=gray!40, linestyle=none]%<br> (-2,-2)(2,-2)(2,2)(-2,2)<br> \psline[linestyle=dashed]{<->}(-2.5,0)(2.5,0)\uput[r](2.5,0){$x$}<br> \psline[linestyle=dashed]{<->}(0,-2.5)(0,2.5)\uput[u](0,2.5,0){$y$}<br> \psline[linecolor=darkgray](-2,-2)(2,2)<br> \psline[linecolor=darkgray](-2,2)(2,-2)<br> \parametricplot[linewidth=1.2pt]{-1.73}{1.73}{t 1 t dup mul add 0.5 exp }<br> \parametricplot [linewidth=1.2pt]{-1.73}{1.73}{t 1 t dup mul add 0.5<br>exp neg }<br> \uput[d](0,-2.5){$z=c<0: x^{2}-y^{2}=-\abs{c}$}}<br><br>\newcommand\xslice{%<br>\pspolygon[fillstyle=solid,<br>fillcolor=blue!10](-1.5,-2.25)(1.5,-2.25)(1.5,2.25)(-1.5,2.25)<br>\psline{<->}(-1.5,0)(1.5,0)\uput[r](1.5,0){$y$}<br>\psline{<->}(0,-2.25)(0,2.25)\uput[u](0,2.25,0){$z$}<br>\psplot[linewidth=1.2pt, linecolor=blue]{-1.5}{1.5}{x dup mul neg}<br>\uput[d](0,-2.5){$x=0:z=-y^{2}$}}<br><br>\newcommand\yslice{%<br>\pspolygon[fillstyle=solid, fillcolor=red!10]%<br>(-1.5,-2.25)(1.5,-2.25)(1.5,2.25)(-1.5,2.25)<br>\psline{<->}(-1.5,0)(1.5,0)\uput[r](1.5,0){$x$}<br>\psline{<->}(0,-2.25)(0,2.25)\uput[u](0,2.25,0){$z$}<br>\psplot[linewidth=1.2pt, linecolor=red]{-1.5}{1.5}{x dup mul}<br>\uput[d](0,-2.5){$y=0:z=x^{2}$}}<br><br><br>\begin{document}<br>\begin{pspicture}(-5,-5.5)(5,1.5)<br>\psset{unit=0.5}<br>\rput(-4.5,0){\zslicepos}<br>\rput(4.5,0){\zsliceneg}<br>\rput(-4.5,-7){\xslice}<br>\rput(4.5,-7){\yslice}<br>\end{pspicture}<br><br>\begin{pspicture*}(-3,-2.5)(3,3)<br>\psset{unit=0.25,lightsrc=40 50 50,viewpoint=18 55 30 rtp2xyz,solidmemory}<br>\psSolid[object=plan,definition=equation,args={[0 0 1 -1]},base=-2 2 -2 2,<br> fillcolor=gray!40,name=zplaneup,ngrid=0.5 0.5,action=none]<br>\psSolid[object=plan,definition=equation,args={[0 0 1 1]},base=-2 2 -2 2,<br> fillcolor=gray!40,name=zplanedown,ngrid=0.5 0.5,action=none]<br>\psSolid[object=plan,definition=equation,args={[1 0 0 0] 90},base=-2 2 -2 2,<br> fillcolor=blue!10,name=xplane,ngrid=0.5 0.5,action=none]<br>\psSolid[object=plan,definition=equation,args={[0 1 0 0]},base=-2 2 -2 2,<br> fillcolor=red!10,name=yplane,ngrid=0.5 0.5,action=none]<br>\psSolid[object=fusion,base=xplane_s yplane_s zplaneup_s zplanedown_s]<br>%<br>\composeSolid%<br>%<br>\psSolid[object=plan,definition=equation,args={[0 1 0 0] 180},base=-2 2<br>-2 2,<br> name=yplane,linewidth=0.5pt,ngrid=0.5 0.5,action=none]<br>\psSolid[object=plan,definition=equation,args={[0 0 1 1]},base=-2 2 -2 2,<br> fillcolor=gray!40,name=zplanedown,ngrid=0.5 0.5,action=none]<br>\psSolid[object=plan,definition=equation,args={[0 0 1 -1]},base=-2 2 -2 2,<br> fillcolor=gray!20,name=zplaneup,ngrid=0.5 0.5,action=none]<br>\psSolid[object=plan,definition=equation,args={[1 0 0 0] 90},base=-2 2 -2 2,<br> name=xplane,ngrid=0.5 0.5,action=none]<br>%<br>\defFunction[algebraic]{ycutfcn}(x){x*x}{}{}%<br>\psProjection[object=courbe,linecolor=red,linewidth=2pt,plan=yplane,<br> range=-1.5 -1,resolution=720,function=ycutfcn,action=draw**]<br>\psProjection[object=courbe,linecolor=red,linewidth=2pt,linestyle=dashed,<br> plan=yplane,range=-1 1.0,resolution=720,function=ycutfcn,action=draw**]<br>\psProjection[object=courbe,linecolor=red,linewidth=2pt,<br> plan=yplane,range=1.0 1.5,resolution=720,function=ycutfcn,action=draw**]<br>%<br>\defFunction[algebraic]{xcutfcn}(y){-y*y}{}{}%<br>\psProjection[object=courbe,linecolor=blue,linewidth=2pt,plan=xplane,<br> range=0.5 1.5,resolution=720,function=xcutfcn,action=draw**]<br>\psProjection[object=courbe,linecolor=blue,linewidth=2pt,linestyle=dashed,<br> plan=xplane,range=-1.5 0.5,resolution=720,function=xcutfcn,action=draw**]<br>%<br>\defFunction[algebraic]{zcutupfcnplus}(t){sqrt(1+t^2)}{t}{}%<br>\psProjection[object=courbeR2,linecolor=black,linewidth=2pt,plan=zplaneup,<br> range=-2 2,resolution=720,function=zcutupfcnplus,action=draw**]<br>%<br>\defFunction[algebraic]{zcutupfcnminus}(t){-sqrt(1+t^2)}{t}{}%<br>\psProjection[object=courbeR2,linecolor=black,linewidth=2pt,plan=zplaneup,<br> range=-2 2,resolution=720,function=zcutupfcnminus,action=draw**]<br>\axesIIID(0,0,0)(3.5,3.5,3.5)<br>\end{pspicture*}<br><br>\end{document}<br><br>Herbert<br><span><x.png></span>_______________________________________________<br>PSTricks mailing list<br><a href="mailto:PSTricks@tug.org">PSTricks@tug.org</a><br>http://tug.org/mailman/listinfo/pstricks<br>archive: http://www.tug.org/pipermail/pstricks/</div></blockquote></div><br></div></body></html>