Generating pander tables in a loop in RMarkdown in Rstudio

Question

I've a set of tables that I'm generating with use of the code similar to the snippet below:

```{r tables, echo=TRUE, eval=TRUE}
require(reshape2); require(pander)
data("mtcars")
data("AirPassengers")

dta_lst <- list(mtcars, AirPassengers)
for (i in 1:length(dta_lst)) {
    pander(melt(head(dta_lst[[i]], n = 2), varnames = c("Something"), 
            value.name = "Something else"), 
           caption = paste("Some table for: ", class(dta_lst[[i]])))
}
```

When I run the code it produces the desired output (naturally, the provided example makes little sense, in my proper data I melt the data in sensible manner):

---------------------------
 variable   Something else 
---------- ----------------
   mpg            21       

   mpg            21       

   cyl            6        

   cyl            6        

   disp          160       

   disp          160       

    hp           110       

    hp           110       

   drat          3.9       

   drat          3.9       

    wt           2.62      

    wt          2.875      

   qsec         16.46      

   qsec         17.02      

    vs            0        

    vs            0        

    am            1        

    am            1        

   gear           4        

   gear           4        

   carb           4        

   carb           4        
---------------------------

Table: Some table for:  data.frame


----------------
 Something else 
----------------
      112       

      118       
----------------

Table: Some table for:  ts

When I attempt to knit the code in Rstudio the pander tables do not appear:

Naturally, without the loop the pander command works just fine and generates the tables that are neatly knitted into a HTML document.

Cherry

In a nutshell, disable the knitr.auto.asis setting in panderOptions and use the results='asis' chunk option in knitr. I will also provide a more detailed answer soon, until then, see this related thread: github.com/Rapporter/pander/issues/142#issuecomment-66619769 – Levan

@daroczig, thanks very much for showing the interest. I used to suggest combination and it worked as advertised. On a more generic matter, will panderOptions('knitr.auto.asis', FALSE) have an impact on how other pander tables area treated in the Rmd file? In addition to the loop described above I'm using pander here and there to derive some more standard tables. – Cherry

Answer 1

In the for loop there is not 'output screen' unless you use the print(x) function.

for (i in 1:4) { i } does not display anything

for (i in 1:4) {print(i)} displays the Numbers 1 2 3 and 4

Solution: In the FOR loop construct the table (using knitt) and assign it into a variable. Then print out this variable using print() function. Remember. You Must add blank lines after and before the var table: use paste function inside print()

Biota

Specifically for pandoc, you need to use cat instead of print. – Sabu