Identical axis scales in parallel coordinate plot

["Wright, Kevin" <kevin.wright@pioneer.com>]

I searched the S-news archive for a way to make the axes of a parallel
coordinate plot have identical scales.  I found no posted solution, so
(having hacked a solution myself) post a solution for future searchers.

To make common common axes for the parallel coordinate plot,
Make a copy of the setup.pd.trellis function in the working directory (that
is, setup.pd.trellis<-setup.pd.trellis) and then edit the copy of the
function.  Change
     if(is.fac[i])
            rx <- c(0, max(tx) + 1)
     else rx <- range(tx)
to the following line
     rx<-r.z

Note: This hack may strangely affect other trellis graphics, so don't forget
to delete the modified setup.pd.trellis function when done with parallel
coordinate plots!


Kevin Wright, Research Scientist
Pioneer Hi-Bred Int'l, x4054.