Re: Reversed axes and connect the dots?

Hi John,

> Q1:In oceanography it's customary to have a "reversed" axis for depth.
> For example, a 2D plot of some measured value (like salinity) ert to
> depth, the origin of the Y axis is at the top of the axis and
> represents the surface of the ocean. Depth increases down the axis
> rather than up from the cartesian origin. Is there any way to tell
> VisAD to draw a reversed axis?

Then you said:

> I also tried reversing the max and min for the axis using
> setRange but that didn't work either--the data points
> disappeared and the axis showed the usual orientation.

visad/examples/ uses repeated calls to setRange()
that reverse axes back and forth, demonstrating that the basic
technique of 'setRange(max, min)' does work to reverse axes.
There must be some other problem.

> Q2: I have succeeded in producing 3D scatter plots where the plot
> symbol is colored by another measured variable. Is there a way in VisAD
> to connect the plotted points with a line segment? If so, can the line
> segment also be colored by the color variable?

To connect the points you need to supply a topology
(i.e., which points are connected) which you would do
via a Gridded3DSet with manifold dimension = 1, which
you would probably use as the domain Set of a FlatField.
Note that this is no longer a scatter plot, though. Now
your data would have a MathType like ((x, y, z) -> v)
and ScalarMaps x -> XAxis, y -> YAxis, z -> ZAxis and
v -> RGB.