Oops, forgot that I can't put HTML in posts directly. The above code will have some incorrect linebreaks which need to be removed for it to work if you cut and paste.
-M. Hampton On May 21, 12:37 am, Marshall Hampton <[email protected]> wrote: > Here's some code which makes 3-D cross-sections of an icosahedron. It > might give some ideas for extensions. > > <pre> > ico = polytopes.icosahedron() > ps = [] > step = 2/10 > for i in srange(-13/10,14/10,step): > sdel = step/20 > mieqs = [x for x in ico.ieqs()] + [[-i,1,1,1],[i+sdel, -1,-1,-1]] > ps.append(Polyhedron(ieqs = mieqs)) > html('<h2>Slices of an icosahedron</h2>') > show(sum([ps[x].render_solid(opacity = .2, rgbcolor = (float(x)/len > (ps),0,1-float(x)/len(ps))) + ps[x].render_wireframe(rgbcolor = (float > (x)/len(ps),0,1-float(x)/len(ps))) for x in range(len(ps))]), frame = > False) > </pre> > On May 15, 5:37 am, [email protected] wrote: > > > Robert Bradshaw wrote: > > > I don't believe we have anything like this yet, but it seems it could > > > be (relatively) easily built on top of the new and very cool 3d > > > implicit plotting functionality. > > > Also, the region parameter should be very useful for this (which > > basically implements nice clipping of 3d objects). > > Seehttp://trac.sagemath.org/sage_trac/ticket/5514fora not-quite-finished > > patch. > > > Jason > > > > - Robert > > > > On May 15, 2009, at 1:42 AM, Jurgis Pralgauskis wrote: > > > >> Hello, > > > >> stereometry needs imagination or more experience, > > >> to understand cross-sections and so on > > > >> I found some interactive example > > >>http://www.learner.org/courses/learningmath/geometry/session9/ > > >> part_c/index.html > > > >> I'd like to have sage interact for solid construction and > > >> cutting_plane parameters > > >> and then view it around via jmol :) > > > >> in school this is mostly needed for parallelepiped or pyramid solids: > > > >> mysolid = SomeSolid(apex_points_3D) > > >> # and I can get, mysolid.surface_planes() > > >> #so I'd expect to have algorithms which detect > > > >> intersection = Intersection(mysolid, cutting_plane) > > >> # we get some 2D polygon, > > >> # probably first analytically find intersection.lines > > >> # and then solve the > > >> # self.segmets = self.endpoints (self.lines , self.mysolid) > > >> # for conic would be some different approach ... > > > >> intersection.fill() # or draw() would draw some lines or color to > > >> show it > > > >> what does sage have already, and what would need to be hacked? > > > >> Thanks in advance :) > > > >> ps.: just for reference > > >>http://en.wikipedia.org/wiki/Cross_section_(geometry) > > >>http://en.wikipedia.org/wiki/Conic_section > > > >> -- > > >> Jurgis Pralgauskis > > >> Don't worry, be happy and make things better ;) --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sage-edu" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-edu?hl=en -~----------~----~----~----~------~----~------~--~---
