mbh86
mbh86

Reputation: 6368

Generate dynamic R-Markdown blocks with data.table objects

I would like like to automate this code with a loop on Species in R Markdown.

---
title: "R Notebook"
output:
  html_document:
    df_print: paged
---

```{r setup, echo=FALSE}
library(knitr)
library(data.table)
iris.dt <- data.table(iris)
iris.species <- stringr::str_to_title(as.character(unique(iris.dt$Species)))
```


### View by Species {.tabset .tabset-fade .tabset-pills}
#### Setosa
```{r}
iris.dt[Species == 'setosa']
```
#### Versicolor
```{r}
iris.dt[Species == 'versicolor']
```
#### Virginica
```{r}
iris.dt[Species == 'virginica']
```

I can generate the tabs by using knit_expand (actually my question is similar to this one Generate Dynamic R Markdown Blocks) but I struggle to display other inputs like data.table. Here is my attempt:

### View by Species automated {.tabset .tabset-fade .tabset-pills}
```{r run-numeric-md, include=FALSE}
out = NULL
for (i in iris.species) {
  out = c(out, knit_expand(text='#### {{i}}'))
}
```

`r paste(knit(text = out), collapse = '\n')`

And here is an overview of the notebook.

enter image description here

Thank you for your help.

Upvotes: 4

Views: 904

Answers (1)

Ralf Stubner
Ralf Stubner

Reputation: 26823

It works for me if I also generate the R blocks:

---
title: "R Notebook"
output:
  html_document:
    df_print: paged
---

```{r setup, echo=FALSE}
library(knitr)
library(data.table)
iris.dt <- data.table(iris)
iris.species <- as.character(unique(iris.dt$Species))
```

 ### View by Species automated {.tabset .tabset-fade .tabset-pills}
```{r run-numeric-md, include=FALSE}
out <- vector(mode = "character", length = length(iris.species))
for (i in iris.species) {
  out[i] <- knit_expand(text = c("#### {{stringr::str_to_title(i)}}",
                                 "```{r, echo = FALSE}",
                                 "iris.dt[Species == '{{i}}']",
                                 "```"))
}
```

`r paste(knit(text = out), collapse = '\n')`

Upvotes: 5

Related Questions