[R] Types in grouped multi-panel (lattice) xyplot

[Deepayan Sarkar]

On 4/10/08, Aaron Arvey <aarvey at cs.ucsd.edu> wrote:
> Apologetic prologue: I've looked through the mailing list for an answer to
>  this (since I'm sure it's trivial) but I have not been able to find a fix.
>
>  So the problem is that I want each group to have a different type of plot.
>  "Probes" should be points and "Segments" should be lines (preferably using
>  the segment plot command, but I've just been trying -- unsuccessfully --
>  to get lines to work).
>
>  To be exact, the data looks like:
>
>  loc      val   valtype      mouse
>  1428  0.1812367 Probes      2
>  1439 -0.4534155 Probes      2
>  1499 -0.4957303 Probes      2
>  1559  0.2448838 Probes      2
>  1611 -0.2030937 Probes      2
>  1788 -0.2235331 Probes      2
>  1428 0.5        Segment     2
>  1439 0.5        Segment     2
>  1499 0.5        Segment     2
>  1559 0.5        Segment     2
>  1611 0.5        Segment     2
>  1788 0.5        Segment     2
>  1428  0.1812367 Probes      1
>  1439 -0.4534155 Probes      1
>  1499 -0.4957303 Probes      1
>  1559  0.2448838 Probes      1
>  1611 -0.2030937 Probes      1
>  1788 -0.2235331 Probes      1
>  1428 0.5        Segment     1
>  1439 0.5        Segment     1
>  1499 0.5        Segment     1
>  1559 0.1        Segment     1
>  1611 0.1        Segment     1
>  1788 0.1        Segment     1
>
>
>    * loc is the x-axis location
>    * val is the y-axis value
>    * valtype is equal to "which" had I been smart and used make.groups
>    * mouse is the 'cond' variable
>
>
>  The plot command I'm currently using is,
>
>  xyplot(val ~ loc | mouse, data = df,
>              groups=valtype
>              aspect=0.5, layout=c(3,3),
>              lty=0, lwd=3, type="p",
>              col=c("black", "blue"),
>              as.table = TRUE)
>
>  which gives me black and blue points for the probes/segments (I've infered
>  alphabetical order for the groups colors).  When I change the type to
>  c("p", "l"), I get
>
>  xyplot(val ~ loc | mouse, data = df,
>              groups=valtype
>              aspect=0.5, layout=c(3,3),
>              lty=0, lwd=3, type=c("p","l"),
>              col=c("black", "blue"),
>              as.table = TRUE)

Try

xyplot(val ~ loc | mouse, data = df,
       groups=valtype,
       type=c("p","l"),
       ## distribute.type = TRUE,
       col=c("black", "blue"))

>  I get the exact same plot.  I've tried using a few of the panel functions
>  I found on the list (I was particularly hopeful for
>  http://tolstoy.newcastle.edu.au/R/help/06/07/30363.html) but I've either
>  been misusing them, or they are not right for what I want to do.
>
>  If anyone knows how to get points and lines in the same panel for the two
>  different groups (probes/segments), I would love to hear about it.
>
>  If you further know how to use the 'segment' plot in panels for the
>  segments, I would really love to hear about it.

Well, panel.segments() draws segments, but you need your data in the
form (x1, y1, x2, y2) for that. With your setup, it's probably easier
to have lines with some NA-s inserted wherever you want line breaks.

-Deepayan