R: why doesn't the cable print inside the for loop?

Question

I am working on a report with rmarkdown and latex. I need to print a group of tables using knitr::kable , but not print when inside a for loop.

This is my code:

 --- title: "project title" author: "Mr. Author" date: "2016-08-30" output: pdf_document: latex_engine: xelatex bibliography: biblio.bib header-includes: - \usepackage{tcolorbox} --- Text and chunks that run ok. ```{r loadLibraries} require(data.table) require(knitr) ``` ## Try to print a group of tables from split ```{r results = "asis"} t1 <- data.table(a = sample(letters, 10, T), b = sample(LETTERS[1:3], 10, T)) t2 <- split(t1, t1$b) for (i in 1:length(t2)){ kable(t2[[i]], col.names = c("A", "B")) } ``` 

It doesn’t matter if I use results = "asis" or even omit it altogether, it doesn't print anything in the document .

I tried to include the kable call in the print ( print ( print(kable(t2[[i]]... ) call and it successfully prints the output in the document, but the format is the same as the standard R request format (preceded by ## , for example), which is pretty ugly .

How to display tables except manually?

### EDIT ###

Some responders redirected me to R knitr print in a loop as a duplicate answer. This is not because, as I said in the previous paragraph, it effectively prints the table, but the format is not expected. The accepted answer (and the associated github thread) really solved the problem.

Answer 1

This issue is resolved here: https://github.com/yihui/knitr/issues/886

All you need is a line break after each print call

 --- title: "project title" author: "Mr. Author" date: "2016-08-30" output: pdf_document: latex_engine: xelatex bibliography: biblio.bib header-includes: - \usepackage{tcolorbox} --- Text and chunks that run ok. ```{r loadLibraries} require(data.table) require(knitr) ``` ```{r results = "asis"} t1 <- data.table(a = sample(letters, 10, T), b = sample(LETTERS[1:3], 10, T)) t2 <- split(t1, t1$b) for (i in 1:length(t2)){ print(kable(t2[[i]], col.names = c("A", "B"))) cat("\n") } ```