I would like to draw $3$ dimensional scatter plots, or more precisely I have a program that gives me the mass distribution in the unit cube with respect to a 3 dimensional equidistant grid. You can interpret this as a continuous relaxation of a $3$ dimensional assignment problem if you want.
Anyway this is just to give you a very brief background since my actual problem is not really concerned with the maths behind the procedure but with the visualization. I have:
- $n$ points in the unit cube $[0,1]^3$
- each of the $n$ points is assigned a "weight" between $0$ and $\frac1n$ (typically a lot of the weights coincide, if there are too many different values, i use the cut command to reduce the range to, say $60$ different values)
And I'd like to plot the $n$ points in a color which corresponds to their weight. Now I found the rgl Package in R which allows me to do exactly that and also provides a very nice interactive plot window but it doesn't seem to allow a "col key" parameter, i.e. I cannot add a continuous color legend to my plot. On the other hand the package plot3D provides a function to do a $3$ dimensional scatterplot and easily allows me to add the col key. However plot3D does not work with interactive plots but merely gives me the option to specify the angle at which I want to look at the cube. In a $3$D setting I strongly prefer the interactive alternative.
Now is there a way to automatically add a continuous color legend to an rgl plot? If not, do you know why this hasn't been implemented? Or would you solve my problem completely different altogether?
P.S. sorry for the formatting, I'm new to SO and the math environment "$" doesn't seem to work here.
