Yes, the string() function fixed the axis labels.
I recompiled Maxima with the patch, but there is still some bug beyond
my ability to fix. This is how to reproduce it, using the
plot_vector_field3d and plot_vector_field functions (there are more
elementary ways, but these functions are at hand since we are
discussing them).
(%i1) plot_vector_field3d([-y,x,z], [x,-1,1],[y,-1,1],[z,-1,1], head_angle=90 )$
Notice that the head angles are not 90 degrees on the vectors. For
some reason, draw3d did not respect that setting. I don't believe it
respected the head_length settings either.
(%i2) plot_vector_field( [-y,x], [x,-1,1], [y,-1,1] )$
(%i3) plot_vector_field3d([-y,x,z], [x,-1,1],[y,-1,1],[z,-1,1], head_angle=90 )$
Now the head angles are 90 degrees. Something happened when we called
draw2d that changed the behavior of draw3d...
Don
On Mon, Dec 13, 2010 at 11:45 AM, Mario Rodriguez
<biomates at telefonica.net> wrote:
>
> Hello Donald,
>
>
> > The labeling of the axes, if nothing else, could be improved, since my
> > code labels them with lisp names (i.e. $X instead of x).
>
> Labels need string values. Write something like
>
> xlabel = string(X[1])
>
> > If you try this code and find the arrow heads on your 3D plots look
> > wrong, I believe it is due to a bug in Maxima, which I reported (with
> > a patch) today:
> > https://sourceforge.net/tracker/?func=detail&atid=104933&aid=3136608&group_id=4933
>
> I've commited your patch to cvs some minutes ago.
>
> > ? You should be able to get acceptable plots if you start Maxima
> > fresh, and try your 3D plots right away, before doing any other
> > plotting. ?(In truth, I suspect there might be a second bug here--not
> > respecting any head_length commands until after draw2d has run--but it
> > works.)
>
> I think your examples work now as expected. Let me know if you get more
> problems.
>
> Thanks for your bug report and patch.
>
> --
> Mario
>