[R] Subsetting within xyplot()

[David Afshartous]

All,

I'm having problems w/ a simple attempt to subset an xyplot.

The first plot below is a plot of y versus x for certain values of a third
categorical variable z.  Now I'd like to further restrict this to certain
values of variable y.  Neither of the two attempts below work.  Any
suggestions much appreciated.  (note: I don't want to merely use ylim since
I have a loess plot and I want this to be calculated w/ the restricted
values).

Thanks,
David 




y = c( 0.4,  0.6, -0.1,  0.3,  0.3, -0.2,  0.7,  0.7,  0.2,  0.0,  0.9,
-0.1,  0.6, -1.1,  0.8, -1.0,  0.4,  0.1,  0.7, -0.2, -0.1, -0.1,  2.2,
0.7,  1.1,  0.2, -0.2, -0.9,  0.4,  0.1, -0.3, -0.4)
x = c(4.1000,  4.9600,  1.2000,  3.9000,  3.1875,  1.9000,  1.8625,
0.7650,  1.5750,  2.4700,  1.6250,  1.5500,  2.3125,  1.3125,  1.0600,
-0.5500,  1.1000,  0.0200, -0.0375,  3.4600,  2.5250,  2.0950,  0.8000,
1.6050, -0.4150, -0.7300,  1.1550,  1.4850,  2.2000,  2.2500,  0.6000,
2.1000)
junk.frm = data.frame(x, y, z = rep(c("D", "P"), 16))

xyplot(y ~ x , data = junk.frm[junk.frm$z =="D",], type = c("g", "p",
"smooth"), pch = 20)

xyplot(y ~ x , data = junk.frm[junk.frm$z =="D",], type = c("g", "p",
"smooth"), pch = 20,
, subset = junk.frm[junk.frm$y < 2, ])
Error in tmp[subset] : invalid subscript type 'list'

xyplot(y ~ x , data = junk.frm[junk.frm$z =="D",], type = c("g", "p",
"smooth"), pch = 20,
data = junk.frm[junk.frm$y < 2 & junk.frm$z =="D", ])
Error in xyplot(y ~ x, data = junk.frm[junk.frm$z == "D", ], type = c("g",
: 
  formal argument "data" matched by multiple actual arguments