matrix/data frame of special characters

Question

I am trying to construct an R matrix/data frame with special characters in it. For example, one cell would contain "2\±5\³" (ie "2±5³").

I need to have Latin lowercase alphabets in the superscript, instead of the number superscript and I was only able to find the Unicode for few alphabets as superscripts .

I am familiar with all the special symbols within the plot functions (eg for labeling axis, titles etc.) but I need the "superscripting" within a matrix.

EDIT: I wanted to do something like this, with only one exception, instead of the 3 in the supescript in 3.5\±2\³ , I want to have latin alphabets.

require(rtf)
rtf<-RTF("./Doc/test_addTable.doc",width=8.5,height=11,font.size=10,omi=c(1,1,1,1))

A = data.frame(Sepal.Length = c(5.1, 4.9, 4.7, 4.6, 5, 5.4),
Sepal.Width = c(3.5, 3, 3.2, 3.1, 3.6, 3.9),
Petal.Length = c(1.4,  1.4, 1.3, 1.5, 1.4, 1.7), Petal.Width = c(0.2, 0.2, 0.2,0.2,0.2, 0.4))

A[1,2] = "3.5\u00B12\u00B3"

addTable(rtf,A,font.size=10,row.names=FALSE,NA.string="-",col.widths=rep(1,4))

done(rtf)

Thank you for your time.

Answer 1

In R there is a system that is like mini-LaTeX but is called "plotmath". It is driven off expression objects and is invoked when an expression hits a text=plotting value. It doesn't really make much sense to have such a matrix if you are not going to plot it, so I will illustrate how to raise character values as superscripts.

?plotmath
plot(1,1)
text( x=c(.8), y=c(1.2), substitute( 2%+-%5^x, list(x="A") ))

That is a bit more complicate than might be needed for a single instance but that is designed to increase generality. You could also do:

text( x=c(.8), y=c(.8), expression(2%+-%5^B) )

If you just want a matrix of plotmath (in character form):

mat <- matrix( c( '2%+-%5^B' , '2%+-%5^C',
                  '2%+-%5^D' , '2%+-%5^B'), 2, 2)
mat

You cannot (or at least I cannot) really construct a true R expression object as a matrix:

 mat <- matrix( expression(2%+-%5^B , 2%+-%5^C,
                   2%+-%5^D , 2%+-%5^B), 2, 2)
     mat
#expression(2 %+-% 5^B, 2 %+-% 5^C, 2 %+-% 5^D, 2 %+-% 5^B)
> str(mat)
length 4 expression(2 %+-% 5^B, 2 %+-% 5^C, 2 %+-% 5^D) ...
 - attr(*, "dim")= int [1:2] 2 2
> mat[1,1]
Error in mat[1, 1] : matrix subscripting not handled for this type
> mat[1]
expression(2 %+-% 5^B)
> mat[2]
expression(2 %+-% 5^C)
> mat[3]
expression(2 %+-% 5^D)

I did manage to get the matrix function to attach dimensions to an expression object but neither print nor [ would honor that dimension. I remain unclear as to the goal. In the rtf package I see the addTable method and I'm wondering if you you really want to have an object that will be printed by an rtf-aware application in "matrix" or tabular form?

Hah.... I think I have it:

 mat <- matrix( c( '2\\+/-5 {\\up3B}' , '2%+-%5 \\up5C',
                   '2%+-%5\\up3B' , '2%+-%5\\up4H'), 2, 2)
 mat
#     [,1]               [,2]          
#[1,] "2\\+/-5 {\\up3B}" "2%+-%5\\up3B"
#[2,] "2%+-%5 \\up5C"    "2%+-%5\\up4H"
 rtf<-RTF("test_addTable.doc",width=8.5,height=11,
                  font.size=10,omi=c(1,1,1,1))
 addTable(rtf, mat)
 done(rtf)

Furthermore I think I fingered out the plusminus sign. Try:

 "2\\u177BD5 {\\up3B}"