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Convert R matrix like `m<-rbind(c("x/(z+1)","x^2/(z+1)"),c("y/(z+1)","y^2/(z+1)"))` to table it to .doc

I want to insert R matrix like m<-rbind(c("x/(z+1)","x^2/(z+1)"),c("y/(z+1)","y^2/(z+1)")) as a table in R Markdown than knit it to .doc.
I would like it in a neat form, such that all cells are separated by lines and all formulas displayed properly. I want to do it automatically from matrix I have.
I am thinking about thous formulas inside the matrix as simple examples of any formula that contains variables and arithmetic operations.
First I tried with more simple expression m<-rbind(c("x","x^2"),c("y","y^2")) with no result.

TeXForm(m)

library(Ryacas)
Sym(m)
TeXForm(m)

I got:

"$x$";

pander(m)

I got:

-------
 A   B 
--- ---
 x  x^2 

 y  y^2
-------

formulas in cells were displayed not properly.

knitr::kable(m)

I got:

|A  |B   |
|:--|:---|
|x  |x^2 |
|y  |y^2 |

It wasn`t displayed properly in .doc.

xtable(m)

I got LaTeX code which I was unable to knit in .doc. But when knitted in pdf formulas in cells were displayed not properly. I also tried print(xtable(m),type="html")
I wasn`t able to knit it to .doc, but in html document it gives results similar to previous.

Replace each element of matrix with LaTeX code

Apymtx<-function(m,f){m1<-m 
for (k in 1:nrow(m)){ for (l in 1:ncol(m)){m1[k,l]<-f(m[k,l])}}
return(m1)}
m<-Apymtx(m, TeXForm)

I got:

[,1]               [,2]                
[1,] "( TeXForm( x ) )" "( TeXForm( x^2 ) )"
[2,] "( TeXForm( y ) )" "( TeXForm( y^2 ) )"

Than I tried to change 'class' of TeXForm(m[1,1]) to 'character' with no result.

How to get table filed with formulas in R Markdown, and knit it to .doc?

Solution

  • You miss that pandoc interprets Tex formulas between the dollar signs. E.g.:

    > pander(data.frame(
+   A = c("$x^2$", "$\\frac{x}{y}$"),
+   B = c("$\\sum_{1}^{n}foobar_i$",
+         "$\\cos (2\\theta) = \\cos^2 \\theta - \\sin^2 \\theta$")))

--------------------------------------
      A                  B            
------------- ------------------------
    $x^2$      $\sum_{1}^{n}foobar_i$ 

$\frac{x}{y}$ $\cos (2\theta) = \cos^2
              \theta - \sin^2 \theta$ 
--------------------------------------

    Renders fine in docx:

    enter image description here

    Edit: based on the question update that made it clearer for me that you want to transform the math formulas to TeX by Ryacas, please see this approach to do so. Unfortunately, I could not get the retclass="unquote" argument working in yacas, that's why the ugly string manipulation:

    > pander(apply(m, c(1, 2), function(x) gsub('\\"|;| ', '', yacas(TeXForm(x))$YacasForm)))

--------------- -------------------
$\frac{x}{z+1}$ $\frac{x^{2}}{z+1}$

$\frac{y}{z+1}$ $\frac{y^{2}}{z+1}$
--------------- -------------------

    MS Word output after calling pander:

    enter image description here