Duncan Murdoch <[EMAIL PROTECTED]> writes:
> On 4/26/2007 7:39 PM, Deepayan Sarkar wrote:
>> Hi,
>>
>> I recently discovered this buglet in lattice: If lattice is _not_
>> attached, I get
>>
>>> lattice::dotplot(~1:10)
>> Error in eval(expr, envir, enclos) : could not find function "bwplot"
>>
>> This happens because of this:
>>
>>> lattice:::dotplot.formula
>> function (x, data = NULL, panel = "panel.dotplot", ...)
>> {
>> ocall <- ccall <- match.call()
>> ccall$data <- data
>> ccall$panel <- panel
>> ccall[[1]] <- as.name("bwplot")
>> ans <- eval.parent(ccall)
>> ans$call <- ocall
>> ans
>> }
>> <environment: namespace:lattice>
>>
>> That is, ccall is eval()-ed in the global environment where bwplot is
>> not visible. While this example is somewhat silly, similar things
>> happen when I try to import lattice from another package.
>>
>> Are there any simple alternatives? I tried
>>
>> ccall[[1]] <- as.name("lattice::bwplot")
>>
>> but that didn't work either.
>
> One way would be to create a new environment with the caller's
> environment as the parent, and put a copy of bwplot in it, i.e.
> something like the following untested code:
>
> function (x, data = NULL, panel = "panel.dotplot", ...)
> {
> ocall <- ccall <- match.call()
> ccall$data <- data
> ccall$panel <- panel
> ccall[[1]] <- as.name("bwplot")
> evalenv <- new.env(parent = parent.frame())
> assign("bwplot", bwplot, envir=evalenv)
> ans <- eval(ccall, envir=evalenv)
> ans$call <- ocall
> ans
> }
>
quote(lattice::bwplot) also seems to work.
+ seth
--
Seth Falcon | Computational Biology | Fred Hutchinson Cancer Research Center
http://bioconductor.org
______________________________________________
R-devel@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-devel
