0) sagenb.com is awesome, especially since Mathematica 7 takes up 100% of my processor at all times under Ubuntu 9.04.
1) When I run: parametric_plot( (cos(t), sqrt(2)*sin(t)) , (t,0,2*pi)) I get a nice 2d parametric plot, with the top of the ellipse clearly hitting close to 1.5 on the y-axis. When I run: parametric_plot3d( (cos(t), 1 , sqrt(2)*sin(t)), (t,0,2*pi)) The top of the ellipse really looks like it's at z=1, and the whole thing looks a lot like a circle. I realize that this is probably not a problem with sage and rather with whatever is doing the plotting, but I thought I should point it out. 2) Also, after clicking and dragging on the 3d plot, I can't type anywhere in firefox (the notebook or the address bar) until I click onto another tab and then back again. This may be a problem with java in my browser not taking the keyboard away from the applet. 3-more of a feature request than an error I guess) I have noticed from googling that there has been some discussion about creating a function from R^n to R^m. I am sure there is some good reason why this isn't the case, but I was curious about whether it would be possible to just automatically map everything over tuples of symbolic expressions, or make a tuple of symbolic expressions a symbolic expression itself. For example, why couldn't diff( (t, 2*t), t) (which gives the error that a tuple is not a symbolic expression) notice that the tuple is a tuple of symbolic expressions, and then just map itself over it to get (1,2). Also, then defining f(x,y) = (2*x, 2*y) seems like it would work. Similarly, what if there was a dot product function which just did the obvious thing when it was given two tuples of symbolic expressions? The reason that I am thinking about this is that it would be really awesome if I could tell my vector calculus class to do a line integral by defining what f(c(t)) =fc(t) and c(t) are and then just: integrate( dot( fc(t), diff( c(t), t), t, 0, 2*pi) rather than something like integrate( vector( (t,t^2,t^3) ).dot_product( diff( vector( (t,t,t) ), t ) ), t,0,2*pi) which is a little less intuitive. -Alden --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
