[R] bwplot and panel.bwplot

[Deepayan Sarkar]

On Friday 02 January 2004 14:29, Patrick Giraudoux wrote:
> Hello,
> 
> I am trying to use "bwplot" to display whisker boxes according to some
> conditioning factors ("age" has two values 1/2). I get the following
> messages:
 
>
> > library(trellis)

I'm not aware of any such package, but I'll assume you are talking about 
something else.

> > bwplot(dvk95~age|site*season,panel=function(x,y){panel.bwplot(x,y)})

Why are you explicitly specifying a panel function ? Doesn't the default 
work ?

> Error in tapply(1:0, structure(list(INDICES = numeric(0)), .Names =
> "INDICES"),  : 
>         arguments must have same length 
> In addition: Warning messages: 
> 1: is.na() applied to non-(list or vector) in: is.na(x) 
> 2: is.na() applied to non-(list or vector) in: is.na(x) 
> 3: is.na() applied to non-(list or vector) in: is.na(x) 
> 4: is.na() applied to non-(list or vector) in: is.na(x) 
> 5: is.na() applied to non-(list or vector) in: is.na(x) 
> 6: is.na() applied to non-(list or vector) in: is.na(x)
> 
> I suspect this may come from not-anwered (NA) combinations of categories
> (data are field data on hazel grouse and the sampling is not balanced).
> Using  "xyplot" however leads to a correct display of data, the "NAs"
> combinations of categories being simply empty in the panel plot.
> 
> Passing na.action = na.omit or similar expressions don't lead to anything
> (actually every vector used has not any NA values).
> 
> Is there a way to get a display with bwplot (and panel.bwplot) in this
> case?
>
> Thanks in advance for any hint,

Difficult to guess without access to the data. Could you send me (offlist) 
your data frame (preferably saved using 'save') along with actual code that 
reproduces the error ?

Deepayan