Dear kcrisman, I think it would be enough to give an example in the tutorial or in the output of "plot3d?". Even more, an example gives kind of a smooth lesson in how really to use the 3dplotting and the ".imag()" or the ".real()" command at the same time. Starting from Jason's examples I did all I wanted to and even more and I am beginning to understand plotting. Examples are better than new commands, because they are way more flexible and they make you play around. Perhaps it would be nice for the user to find an example how to plot graphs like these
http://mathworld.wolfram.com/ModifiedBesselFunctionoftheSecondKind.html in the outputs of "bessel_X?". In this case I succeded in generating some pictures, but they don't look like the ones in mathworld. (But I am not asking for support in this respect.) One thing I am missing (or simply not understanding) is 3dplotting without automatically scaled up range of the function value. Jmol and Sage seem to try to plot the whole graph even at singularities, then give up (at a level I don't know how to fix) but leave the picture with the scaled up value range. Use the link above to see what I mean would be useful sometimes. There the value range is simply cut at some point. In the german wikipedia article on the exponential funcion it is done in a similar way by Maple and the whole picture is scaled equal in all dimensions. But I am going to make a new support question out of that. Thanks a lot. Yours, littlemathteacher On 31 Mai, 04:01, kcrisman <kcris...@gmail.com> wrote: > Ironically, I did something just like this at a talk this week. But I > used something like > > lambda x,y: abs(zeta(x+i*y)) > > (actually not that, but I hope that will work). > > At least one of these should really be implemented as complexplot3d or > something like that. Does that seem like a useful function to have > around? > > - kcrisman > > On May 30, 9:13 pm, littlemathteacher <relational...@gmail.com> wrote: > > > > > Thanks a lot. Much simpler than I thought it would be. Very fine > > instructive example. > > Yours, littlemathteacher. > > > On 30 Mai, 17:49, Jason Grout <jason-s...@creativetrax.com> wrote: > > > > littlemathteacher wrote: > > > > Dear Supporters, > > > > > first of all thanks to you all for doing such a great support job to > > > > me so far. > > > > > Now I want to make complex analysis visible and to plot 3d-graphics > > > > either of real or imaginary parts of functions. > > > > > The first step would be to plot the exponential function just like in > > > > the german or the us wikipedia article, later to show the branch cuts > > > > like in > > > > >http://mathworld.wolfram.com/BranchCut.html > > > > > or the gamma function like in > > > > >http://mathworld.wolfram.com/GammaFunction.html. > > > > > The reason why my attemps fail might lie somwhere in the defining of > > > > variables and in the picking out of the real or the imaginary part. > > > > > I guess all I need is one working example of how to 3dplot let's say > > > > complexplane X real part of the function value. > > > > > Starting from that example I could do the rest myself, but I didn't > > > > find one yet. > > > > > Could you please post a link to an example? > > > > And here's the imaginary part: > > > > sage: plot3d(lambda x,y: arcsin(x+y*I).imag(), (-2,2), (-2,2)) > > > > Jason > > > -- > > > Jason Grout --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
