[R] Plotmath bug or my misunderstanding?

[Duncan Murdoch]

On 12-05-13 12:27 AM, David Winsemius wrote:
>
> On May 12, 2012, at 6:27 PM, Peter Ehlers wrote:
>
>> Hi Bert,
>>
>> I think the 'cex=' argument applies to the outermost 'atop()'.
>> It then applies that size specification to each of the two
>> components of the atop(a,b). If one of the components is itself
>> another atop(a,b), then the individual parts are sized downward
>> to produce the required cex for the unit.
>>
>> As for the 'cex=1:2' specification, only the first value is used.
>
> Isn't there also a 0.67 factor being applied to whatever was the
> "outside" size prior to being used for the atop arguments? So the
> inner atop arguments get that applied twice if I understand correctly.
>
> text(1,1,labels=expression(atop(
>                  atop("top level one", "top level two"),
>                  "another level")
>        ) )
>
>
> I did notice that the cr-linefeed (perhaps unintentionally being
> inserted by a mail client) seemed to be "working" at least on my Mac :
>
> plot(1,1)
> text(1,1,labels=expression("another
> level")
>        )
>
> Whereas it is well known that "\n" will appear as two characters, \n,
> and not be interpreted as a special.

I think that only works when the newline (which could equally be \n) is 
within a string; if you want a symbol over another symbol you need the atop.

I.e.

plot(1,1)
text(1,1,labels=expression("another\nlevel"))

is the same as what you typed, but

plot(1,1)
text(1,1,labels=expression(paste("another","\n", "level")))

won't do anything useful.

Duncan Murdoch