[R] Using latticeExtra as.layer function with different number of plot panels

[sbihorel]

Thanks David,

I was hoping for something a little bit more generic and less 
case-by-case basis.

Sebastien

On 7/30/2015 3:51 PM, David Winsemius wrote:
> On Jul 30, 2015, at 8:37 AM, sbihorel wrote:
>
>> Hi,
>>
>> When the as.layer function is used to overaly 2 lattice plots, there seems to be an assumption that the data used in both plots will generate the same number of panels (and, I believe, in the same order). In case the data used in the plot within the as.layer call is incomplete , data may be plotted on the "wrong" panel, and data seem to get re-used on the last panel(s). See what happens in the example code below when the records with state.region=="South" are dropped...
>>
>> Is there a trick to overlay panel based upon the conditioning variable value rather than the panel order?
>>
>> require(lattice)
>> require(latticeExtra)
>> state2 <- state <- data.frame(state.x77,state.region)
>> state2$Income <- sample(state2$Income)
>> state3 <- state2[which(state2$state.region!="South"),]
>> foo <- xyplot(Income~Population|state.region,data=state,main='foo')
>> foo
>>
>> bar <- update(foo,main='bar') + as.layer(xyplot(Income~Population|state.region,data=state2,col='red'))
>> bar
>>
>> bar2 <- update(foo,main='bar2') + as.layer(xyplot(Income~Population|state.region,data=state3,col='red'))
>> bar2
> I don't know if this works using the `+.lattice` function but it is possible to selectively update panels using `trellis.focus`
>