R help - Jul 2004 - lattice variable by page

Hi,

Using lattice's xyplot, is it possible to specify a variable to group
plots by page.  For example, if I have

xyplot(y~x|A*B*C)

could I get a page created for each unique value in
variable C ?  I am hoping to avoid having pages with the same strip above
each plot on a page.

Thanks,

M

Matt Pocernich
NCAR - Research Applications Program
303-497-8312

Matt Pocernich wrote:
> Hi,
> 
> Using lattice's xyplot, is it possible to specify a variable to group
> plots by page.  For example, if I have
> 
> xyplot(y~x|A*B*C)
> 
> could I get a page created for each unique value in
> variable C ?  I am hoping to avoid having pages with the same strip above
> each plot on a page.
> 
> Thanks,
> 
> M
> 
Others may have a better solution, but when I've done this in the past I 
used a for loop with subset:

# assuming C is a factor to use nlevels
for(ci in nlevels(C)) {
   pl <- xyplot(y ~ x | A * B,
                subset = C == ci,
                main = paste("C ==", ci))
   print(pl)
}

HTH,
--sundar

On Wednesday 28 July 2004 16:36, Matt Pocernich wrote:
> Hi,
> 
> Using lattice's xyplot, is it possible to specify a variable to group
> plots by page.  For example, if I have
> 
> xyplot(y~x|A*B*C)
> 
> could I get a page created for each unique value in
> variable C ?  I am hoping to avoid having pages with the same strip above
> each plot on a page.
If I understand you correctly (which I'm not sure I do), then no, not 
directly. But you can do the following (assuming C is a factor):


for (l in levels(C)) {
  print(xyplot(y ~ x | A * B, subset = C == l))
}

Is that what you are looking for?

Deepayan