[R] lattice: how to "center" a subtitle?

[Marius Hofert]

Dear all,

many thanks, that helped a lot!

Cheers,

Marius

On 2011-04-04, at 19:58 , David Winsemius wrote:

> 
> On Apr 4, 2011, at 1:27 PM, Marius Hofert wrote:
> 
>> Dear David,
>> 
>> do you know how to get plotmath-like symbols in both rows?
>> I tried s.th. like:
>> 
>> lab <- expression(paste(alpha==1, ", ", beta==2, sep=""))
>> xlab <- substitute(expression( atop(lab==lab., bold(foo)) ), list(lab.=lab))
>> xyplot(0 ~ 0, xlab = xlab)
> 
> I _did_ have plotmath functions in both rows: But here is your solution:
> 
> xyplot(0 ~ 0,  xlab =
>    expression( atop(paste(alpha==1, "   ", beta==2), bold(bla) )) )
>      )
> 
> Note that `paste` in plotmath is different than `paste` in regular R. It has no `sep` argument. I did try both substitute and bquote on you externally expression,  but lattice seems to be doing some non-standard evaluation and I never got it to "work". Using what I thought _should_ work, does work with `plot`:
> 
> > x=1;y=2
> > plot(0 ~ 0, xlab = bquote( atop(alpha==.(x)*","~beta==.(y), bold(foo) ) )
> + )
> 
> But the same expression throws an error with xyplot:
> > x=1;y=2
> > xyplot(0 ~ 0, xlab = bquote( atop(alpha==.(x)*","~beta==.(y), bold(foo) ) )
> + )
> Error in trellis.skeleton(formula = 0 ~ 0, cond = list(1L), aspect = "fill",  :
>  could not find function "atop"
> 
> -- 
> David.
> 
> 
>> 
>> Cheers,
>> 
>> Marius
>> 
>> On 2011-04-04, at 18:59 , David Winsemius wrote:
>> 
>>> 
>>> On Apr 4, 2011, at 12:45 PM, Marius Hofert wrote:
>>> 
>>>> Dear David,
>>>> 
>>>> I intended to use another x-label. But your suggestion brings me to the idea of just using a two-line xlab, so s.th. like
>>>> print(xyplot(0 ~ 0, xlab.top = "This title is now 'centered' for the human's eye", xlab = "but subtitles are _now_ centered\nbla", scales = list(alternating = c(1,1), tck = c(1,0))))
>>> 
>>> And if you wanted different fontface (underline, italic or bold) then you could use plotmath expressions:
>>> 
>>> xyplot(0 ~ 0, xlab.top = "This title is now 'centered' for the human's eye", xlab = expression( atop(but~subtitles2~are~underline(now)~centered, bold(bla) )), scales = list(alternating = c(1,1), tck = c(1,0)))
>>> 
>>> -- 
>>> David.
>>> 
>>>> 
>>>> Thanks!
>>>> 
>>>> Cheers,
>>>> 
>>>> Marius
>>>> 
>>>> On 2011-04-04, at 16:47 , David Winsemius wrote:
>>>> 
>>>>> 
>>>>> On Apr 4, 2011, at 7:39 AM, Marius Hofert wrote:
>>>>> 
>>>>>> Dear expeRts,
>>>>>> 
>>>>>> I recently asked for a real "centered" title (see, e.g., http://tolstoy.newcastle.edu.au/R/e13/help/11/01/0135.html).
>>>>>> A nice solution (from Deepayan Sarkar) is to use "xlab.top" instead of "main":
>>>>>> 
>>>>>> library(lattice)
>>>>>> trellis.device("pdf")
>>>>>> print(xyplot(0 ~ 0, xlab.top = "This title is now 'centered' for the human's eye", sub = "but subtitles are not centered", scales = list(alternating = c(1,1), tck = c(1,0))))
>>>>>> dev.off()
>>>>> 
>>>>> library(lattice)
>>>>> trellis.device("pdf")
>>>>> print(xyplot(0 ~ 0, xlab.top = "This title is now 'centered' for the human's eye", xlab = "but subtitles are _now_ centered", scales = list(alternating = c(1,1), tck = c(1,0))))
>>>>> dev.off()
>>>>> 
>>>>> 
>>>>> (I realize that those are not really subtitles by a 'lab', but that appears acceptable in your current test case.)
>>>>> 
>>>>>> 
>>>>>> My question is whether there is something similar for *sub*titles [so something like "xlab.bottom"]? As you can see from the plot, the subtitle does not seem to be "centered" for the human's eye. I would like to center it according to the x-axis label.
>>>>>> 
>>>>> 
>>>>> 
>>>>> David Winsemius, MD
>>>>> West Hartford, CT
>>>>> 
>>>> 
>>> 
>>> David Winsemius, MD
>>> West Hartford, CT
>>> 
>> 
> 
> David Winsemius, MD
> West Hartford, CT
>