[R] Increasing space for main title in a lattice (xyplot()) graphics.

[Deepayan Sarkar]

Hi Bert,

You are right that the general solution is for 'main' to be a (grid)
grob. It is not clear (to me) what the "height" of a textGrob with
multiple labels should be, but the following gives reasonable results:

xyplot(1 ~ 1,
       main = textGrob(c("The quick brown fox jumped", "over the lazy dog"),
                       x = unit(0.5, "npc"), y = unit(c(0.75, 0.25), "cm")))

I'm guessing your first attempt was with the default units ("npc") for y.

The correct grob (allowing more detailed control) to use for complex
grid objects is a frameGrob.

lattice does have an interface to create (simple) frameGrobs, for
constructing legends. This can be (ab)used as follows:

xyplot(1 ~ 1,
       main = draw.key(key = list(text = list(c("The quick brown fox jumped",
                                                "over the lazy dog"),
                                              font = c(1, 2), col = c(2, 3)))))

-Deepayan

On Thu, Feb 13, 2020 at 11:36 AM Bert Gunter <bgunter.4567 using gmail.com> wrote:
>
> OK. Now for a tougher problem: how to make the first line bold font and the second line normal font (and/or different colors)?
>
> My reading of the docs did not reveal how to do it, but I found a way using a textGrob for the title (i.e. main ). But it's tricky, as the "obvious solution" of using different y values for the lines caused lattice to enlarge the title viewport too much, shrinking the graph panels so that details were lost. I think I have found a way to avoid this and make it work, but I'll delay giving my somewhat clumsy "solution" until some of you have a chance to find a more sensible approach, if you care to try.
>
> Bert
>
> Bert Gunter
>
> "The trouble with having an open mind is that people keep coming along and sticking things into it."
> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
>
>
> On Wed, Feb 12, 2020 at 9:19 PM Deepayan Sarkar <deepayan.sarkar using gmail.com> wrote:
>>
>> On Thu, Feb 13, 2020 at 10:39 AM Richard M. Heiberger <rmh using temple.edu> wrote:
>> >
>> > It works as anticipated for me
>> >
>> > > xyplot(1 ~ 1,
>> > +             main="The quick brown fox jumped\n over the lazy dog.")
>> > > xyplot(1 ~ 1,
>> > +             main="The quick brown fox jumped over the lazy dog.")
>> >
>> > Something else you are doing is probably causing the difficulty.
>>
>> Yes, the necessary space should be automatically allocated. Details of
>> version / device might help diagnosing the problem.
>>
>> -Deepayan
>>
>> >
>> > Rich
>> >
>> > On Wed, Feb 12, 2020 at 11:59 PM Rolf Turner <r.turner using auckland.ac.nz> wrote:
>> > >
>> > >
>> > > I'm trying to do an xyplot() with a longish main title that I'd like to
>> > > split into two lines, something like
>> > >
>> > >      xyplot(<whatever>,
>> > >             main="The quick brown fox jumped\n over the lazy dog.")
>> > >
>> > > When I do this I only get the last half, i.e. the "over the lazy dog."
>> > > bit, and the first half doesn't appear.
>> > >
>> > > In base graphics I'd handle this sort of thing by increasing the third
>> > > entry of the "mar" parameter.
>> > >
>> > > How can increase the space allocated for the title in lattice graphics?
>> > > I've done a substantial amount of Googling and can't find anything
>> > > helpful.  I've fiddled about with trellis.par.set() and cannot seem to
>> > > get any effect.
>> > >
>> > > Could someone please give my poor feeble brain some guidance?  Ta.
>> > >
>> > > cheers,
>> > >
>> > > Rolf Turner
>> > >
>> > > --
>> > > Honorary Research Fellow
>> > > Department of Statistics
>> > > University of Auckland
>> > > Phone: +64-9-373-7599 ext. 88276
>> > >
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>>
>> ______________________________________________
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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.