[vtkusers] Two parallel coords chart questions

[Marcus D. Hanwell]

On Fri, Apr 23, 2010 at 9:56 AM, Eric E. Monson <emonson at cs.duke.edu> wrote:

> Hey again,
>
> I just noticed that vtkAxis has a SetBehavior() method, so I've been trying
> to set it to 2 so that auto-scaling won't happen. When the chart first shows
> up on the screen I can tell it's using my min/max I've set (along with the
> "nice" bounds you're calling with axis->AutoScale()), but almost immediately
> all the axes rescale themselves to the bounds of each individual table
> column. I can't find where in the chart code the axis Behavior=2 is getting
> overridden...
>

I just pushed a fix (commit f14bcc3) that should address this. With all of
the development work on the charts I overlooked the check to see if the axes
should be scaled. Once you pull the latest sources from git (or apply that
patch) you should get the expected behavior.

>
> If you have any ideas I'd appreciate it.
>
> (Also, it might be a nice feature to have a "set all axes to the same
> (auto) range" feature, and maybe an option to not call axis->AutoScale() if
> people want to set their own custom tick positions.)
>

Yes, I had wondered about the value of adding such convenience functions. I
am still quite new to parallel coordinates, and would love to see more use
cases for them. Is the application you are working on going to be available?
I would love to see what you are doing with the charts I have been working
on.

Currently the convert selection technique you are using is the best
approach. We may add more to the charts in the future, but have some bigger
questions to answer first with regards to data structure and feeding through
finer grained selections.

Marcus

>
> On Apr 22, 2010, at 4:47 PM, Eric E. Monson wrote:
>
> > Hey Marcus,
> >
> > I figured out how to use vtkConvertSelection, so #1 isn't as urgent
> (although if there's something built in to the chart it would be good to
> know about).
> >
> > #2 is still an issue, when you get a chance.
> >
> > Thanks,
> > -Eric
> >
> >
> > On Apr 22, 2010, at 3:21 PM, Eric E. Monson wrote:
> >
> >> Hey Marcus,
> >>
> >> I'm back to trying to incorporate the parallel coordinates chart into my
> vis project and I have a couple of quick questions:
> >>
> >> 1. If the table I'm using for plotting has PedigreeIds, is there any way
> to get the selection to return this instead of indices? I tried creating my
> own annotation link with the correct ContentType and setting that as the
> chart's annotation link, but it still comes back as Indices... (I'm still
> not great with the selection stuff -- maybe there's an easy way to convert
> the type by using the SelectionNode itself, or maybe I need to use
> vtkConvertSelection?)
> >>
> >> 2. Is there a way to manually set the axis ranges? In this case I want
> to be able to compare the scales of the variables across all axes, so I'd
> like all the axes to have the same range. I tried
> chart.GetAxis(i).SetMaximum() and Minimum, but it looks like your auto-scale
> axes kung-fu is too strong for my "poke at it with a stick" technique... :)
>  Is there any way around this right now?
> >>
> >> Thanks a lot,
> >> -Eric
> >>
> >> ------------------------------------------------------
> >> Eric E Monson
> >> Duke Visualization Technology Group
> >>
> >> _______________________________________________
> >> Powered by www.kitware.com
> >>
> >> Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
> >>
> >> Please keep messages on-topic and check the VTK FAQ at:
> http://www.vtk.org/Wiki/VTK_FAQ
> >>
> >> Follow this link to subscribe/unsubscribe:
> >> http://www.vtk.org/mailman/listinfo/vtkusers
> >
> > _______________________________________________
> > Powered by www.kitware.com
> >
> > Visit other Kitware open-source projects at
> http://www.kitware.com/opensource/opensource.html
> >
> > Please keep messages on-topic and check the VTK FAQ at:
> http://www.vtk.org/Wiki/VTK_FAQ
> >
> > Follow this link to subscribe/unsubscribe:
> > http://www.vtk.org/mailman/listinfo/vtkusers
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20100423/706a8415/attachment.htm>