[R] update'ing trellis object

[David Winsemius]

I wonder if you noticed that you had managed to create a "fig" object  
that has two "inside" lists by specifying first a key "list" which  
required a legend list, and then specifying a "legend" list that also  
had a key function? The solution to your specific request by Kortschak  
"nulled-out" the second of those.

-- 
David

On Oct 3, 2009, at 10:35 PM, David Winsemius wrote:

>
> On Oct 3, 2009, at 7:05 PM, Sebastian P. Luque wrote:
>
>> Hi,
>>
>> I thought the following would only remove the legend element of a
>> trellis object, but it actually removes both the legend and key
>> elements:
>>
>> ---<--------------------cut here--------------- 
>> start------------------->---
>> fig <- xyplot(Sepal.Length ~ Petal.Length, groups=Species, data=iris,
>>             key=list(x=1, y=0.02, corner=c(1, 0), size=3, between=1,
>>               text=list(levels(iris$Species))),
>>             legend=list(inside=list(fun="draw.key", x=0, y=1,
>>                           corner=c(0, 1),
>>                           args=list(key=list(text=list("a)",  
>> cex=1.5)),
>>                             draw=FALSE))))
>> update(fig, legend=NULL)
>> ---<--------------------cut here--------------- 
>> end--------------------->---
>>
>> Is this the right way to remove an element from the object, using
>> update.trellis()?  Thanks.
>>
> It probably depends on the element. In the case of "key", it is a  
> descendant of the legend list so when you make legend NULL you are  
> wiping out all of its descendants as well:
> > str(fig)
> List of 43
> snipped a few lines
> $ legend           :List of 2
>  ..$ inside:List of 5
>  .. ..$ fun   : chr "draw.key"
>  .. ..$ args  :List of 2
>  .. .. ..$ key :List of 6
>  .. .. .. ..$ x      : num 1
>  .. .. .. ..$ y      : num 0.02
>  .. .. .. ..$ corner : num [1:2] 1 0
>  .. .. .. ..$ size   : num 3
>  .. .. .. ..$ between: num 1
>  .. .. .. ..$ text   :List of 1
>  .. .. .. .. ..$ : chr [1:3] "setosa" "versicolor" "virginica"
>  .. .. ..$ draw: logi FALSE
>  .. ..$ x     : num 1
>  .. ..$ y     : num 0.02
>  .. ..$ corner: num [1:2] 1 0
>  ..$ inside:List of 5
>  .. ..$ fun   : chr "draw.key"
>  .. ..$ x     : num 0
>  .. ..$ y     : num 1
>  .. ..$ corner: num [1:2] 0 1
>  .. ..$ args  :List of 2
>  .. .. ..$ key :List of 1
>  .. .. .. ..$ text:List of 2
>  .. .. .. .. ..$    : chr "a)"
>  .. .. .. .. ..$ cex: num 1.5
>  .. .. ..$ draw: logi FALSE
>
>>
>> Cheers,
>>
>> -- 
>> Seb
>>
>> ______________________________________________
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>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

David Winsemius, MD
Heritage Laboratories
West Hartford, CT