Import and manipulate R Scripts programmatically / Convert .R to .Rmd - r

I have an R Script that I would like to import from within a different R-script, manipulate it's content (search and replace) and save with a different extension (.rmd).
This is how the example.R File would look before manipulation:
# A title
# chunkstart
plot(1,1)
# chunkend
and this is how example.Rmd it would look after manipulation: replaced "# chunkstart" and "# chunkend" with ```{r} and ```, respectively.
# A title
```{r}
plot(1,1)
```
I've been searching for methods to do this, but so far have found none. Any ideas?

I'm sure that you can do it using regex with less lines of code.
However its should solve your problem.
library(magrittr)
readLines('example.R') %>%
stringr::str_replace("# chunkstart", "```{r}") %>%
stringr::str_replace("# chunkend", "```") %>%
writeLines("example.Rmd")
With the following lines of code you will be able to apply this "operation" in every .R file inside /path_to_some_directory
lapply(list.files('/path_to_some_directory', pattern = ".R$",
full.names = TRUE), function(data) {
readLines(data) %>%
stringr::str_replace("# chunkstart", "```{r}") %>%
stringr::str_replace("# chunkend", "```") %>%
writeLines(paste0(data, "md"))
})
Hope it helps!

I think ?knitr::spin is a relevant answer to the question (specifically asking for ideas), or at least a useful alternative to consider.
You'd have to slightly reformat the input, but the benefits would be a built-in, much richer and versatile way to deal with chunk options and formatting.
Here's what an annotated R script might look like (with spin's default regexs),
#' ## A title
#' first chunk
#- fig.width=10
plot(1,1)
# some text
#' another chunk
plot(2,2)
and the output Rmd reads,
## A title
first chunk
```{r fig.width=10}
plot(1,1)
# some text
```
another chunk
```{r }
plot(2,2)
```

Related

Rmarkdown backticks inside inline code / inconsistent behavior with usual code chunks

This works in a usual code chunk in R markdown:
m1_aov <- anova(m1)
m1_aov$`Sum Sq`[2] %>% round(3)
Unfortunately, using the latter in inline code breaks the knitr parser down
`r m1_aov$`Sum Sq`[2] %>% round(3)`
Indeed, it also breaks Stackoverflow.
I looked at this related question but could not infer a working solution to my problem. Any hint?
Expanding the comment with a working example:
---
output: html_document
---
```{r setup, include=FALSE}
knitr::opts_chunk$set(echo = TRUE)
```
## R Markdown
```{r}
a <- tibble::tibble(`a column` = 1:10) # using tibble to get a column name with a white space
m <- mean(a$`a column`)
```
Mean is `r m`
To me this looks like a neat trick because it avoids to include unecessary long code inside the text, and do not create the problem you are facing at the (small) cost of creating new objects.
The output:

Write multiple PDF object in one file using magick in R

I am working to stick two PNGs side by side and then convert the concatenated object to a PDF using the code below. Now how can I write all the PDF objects as pages in a single file? I tried to save all the objects in a list and then pass the list to image_write(), but it did not work.
library(magick)
vec_out <- list()
for(i in 1:length(all_stims)){
stim <- all_stims[i]
img1 <- image_read(file.path(figures_folder, "across_cluster_heatmaps", paste0("bendall_",stim,".png")))
img2 <- image_read(file.path(figures_folder, "across_cluster_heatmaps", paste0("farmer_", stim,".png")))
imgs <- c(img1, img2)
imgs <- image_append(imgs)
imgs_pdf <- image_convert(imgs)
vec_out[[i]] <- imgs_pdf
}
image_write(vec_out, path = file.path(figures_folder, "test.pdf"), format = "pdf")
Any suggestions would be helpful. Thanks.
Couldn't you write a knitr-document instead, or as rmarkdown-file?
I could not run your code, since it's not reproducible.
A mini example in rmarkdown:
The following code produces 3 plots in a for-loop.
By choosing result = 'asis' as option and by inserting
cat("\n\n\\pagebreak\n") in the for-loop, every output is printed on a separate page.
---
title: "Test page break between two figures"
output: pdf_document
---
```{r, echo=FALSE, results='asis'}
for (i in 1:3) {
print(plot(1:i, rnorm(i)))
cat("\n\n\\pagebreak\n")
}
```
I suggest doing something as mentioned above, instead of creating in a first step all pdf-files separately and glue them together in a second step.

RMarkdown: ggplot into a table

There are already a few questions considering ggplots in RMarkdown but none has answered my question as how to put a ggplot into a table with kable() by knitr.
I ve tried this link:
How can I embed a plot within a RMarkdown table?
But have not had any luck so far. Any ideas?
The idea was to put all plots into a list with
a<-list(p1,p2,p3...)
and then having the table with
{r}kable(a)
Additional text should also be able to be included
b<-("x","y","z",...)
kable (c(a,b),col.names=c())
Thanks for your help
Frieder
I experimented some with this and the following is the best I could come up with. This is a complete markdown document you should be able to paste into RStudio and hit the Knit button.
Two relevant notes here.
Setting the file links directly into kable doesn't work as it is wrapped in html such that it is interpreted as text, so we need to gsub() it in. An alternative is to set kable(..., escape = FALSE), but it is a risk that other text might cause problems.
Also, the chunk option results = 'asis' is necessary to have the print(kab) return raw html.
I don't know if these are problems for the real application.
---
title: "Untitled"
author: "me"
date: "02/06/2020"
output: html_document
---
```{r, results = 'asis'}
library(ggplot2)
library(svglite)
n <- length(unique(iris$Species))
data <- split(iris, iris$Species)
# Create list of plots
plots <- lapply(data, function(df) {
ggplot(df, aes(Sepal.Width, Sepal.Length)) +
geom_point()
})
# Create temporary files
tmpfiles <- replicate(n, tempfile(fileext = ".svg"))
# Save plots as files, get HTML links
links <- mapply(function(plot, file) {
# Suit exact dimensions to your needs
ggsave(file, plot, device = "svg", width = 4, height = 3)
paste0('<figure><img src="', file, '" style = "width:100%"></figure>')
}, plot = plots, file = tmpfiles)
# Table formatting
tab <- data.frame(name = names(plots), fig = paste0("dummy", LETTERS[seq_len(n)]))
kab <- knitr::kable(tab, "html")
# Substitute dummy column for figure links
for (i in seq_len(n)) {
kab <- gsub(paste0("dummy", LETTERS[i]), links[i], kab, fixed = TRUE)
}
print(kab)
```
I have found my way around it as described in the link I posted.
I. Saved my plot as a picture
II. Used sprintf() to insert picture into table with this command from Rmarkdown:
![](path/to/file)
Poor, but it works. If anybody finds a solution, I will always be interested in smart coding.

rstudio hangs and aborts with rmarkdown loop

I have several datasets each of which have a common grouping factor. I want to produce one large report with separate sections for each grouping factor. Therefore I want to re-run a set of rmarkdown code for each iteration of the grouping factor.
Using the following approach from here doesnt work for me. i.e.:
---
title: "Untitled"
author: "Author"
output: html_document
---
```{r, results='asis'}
for (i in 1:2){
cat('\n')
cat("#This is a heading for ", i, "\n")
hist(cars[,i])
cat('\n')
}
```
Because the markdown I want to run on each grouping factor does not easily fit within one code chunk. The report must be ordered by grouping factor and I want to be able to come in and out of code chunks for each iteration over grouping factor.
So I went for calling an Rmd. with render using a loop from an Rscript for each grouping factor as found here:
# run a markdown file to summarise each one.
for(each_group in the_groups){
render("/Users/path/xx.Rmd",
output_format = "pdf_document",
output_file = paste0(each_group,"_report_", Sys.Date(),".pdf"),
output_dir = "/Users/path/folder")
}
My plan was to then combine the individual reports with pdftk. However, when I get to the about the 5th iteration my Rstudio session hangs and eventually aborts with a fatal error. I have ran individually the Rmd. for the grouping factors it stops at which work fine.
I tested some looping with the following simple test files:
.R
# load packages
library(knitr)
library(markdown)
library(rmarkdown)
# use first 5 rows of mtcars as example data
mtcars <- mtcars[1:5,]
# for each type of car in the data create a report
# these reports are saved in output_dir with the name specified by output_file
for (car in rep(unique(rownames(mtcars)), 100)){
# for pdf reports
rmarkdown::render(input = "/Users/xx/Desktop/2.Rmd",
output_format = "pdf_document",
output_file = paste("test_report_", car, Sys.Date(), ".pdf", sep=''),
output_dir = "/Users/xx/Desktop")
}
.Rmd
```{r, include = FALSE}
# packages
library(knitr)
library(markdown)
library(rmarkdown)
library(tidyr)
library(dplyr)
library(ggplot2)
```
```{r}
# limit data to car name that is currently specified by the loop
cars <- mtcars[rownames(mtcars)==car,]
# create example data for each car
x <- sample(1:10, 1)
cars <- do.call("rbind", replicate(x, cars, simplify = FALSE))
# create hypotheical lat and lon for each row in cars
cars$lat <- sapply(rownames(cars), function(x) round(runif(1, 30, 46), 3))
cars$lon <- sapply(rownames(cars), function(x) round(runif(1, -115, -80),3))
cars
```
Today is `r Sys.Date()`.
```{r}
# data table of cars sold
table <- xtable(cars[,c(1:2, 12:13)])
print(table, type="latex", comment = FALSE)
```
This works fine. So I also looked at memory pressure while running my actual loop over the Rmd. which gets very high.
Is there a way to reduce memory when looping over a render call to an Rmd. file?
Is there a better way to create a report for multiple grouping factors than looping over a render call to an Rmd. file, which doesn't rely on the entire loop being inside one code chunk?
Found a solution here rmarkdown::render() in a loop - cannot allocate vector of size
knitr::knit_meta(class=NULL, clean = TRUE)
use this line before the render line and it seems to work
I am dealing with the same issue now and it's very perplexing. I tried to create some simple MWEs but they loop successfully on occasion. So far, I've tried
Checking the garbage collection between iterations of rmarkdown::render. (They don't reveal any special accumulations.)
Removing all inessential objects
Deleting any cached files manually
Here is my question:
How can we debug hangs? Should we set up special log files to understand what's going wrong?

RMarkdown render to Notebook with child chunks included

I'm after a way to render an Rmd document (that contains references to various "child" files) to a self-contained R Notebook without these dependencies.
At the moment, the .Rmd code chunks are located throughout a number of .R, .py and .sql files and are referenced in the report using
```{r extraction, include=FALSE, cache=FALSE}
knitr::read_chunk("myscript.R")
```
followed by
```{r chunk_from_myscript}
```
as documented here.
I've done this to avoid code duplication and to allow for running the source files separately however these code chunks are only executable in the report via a call to knit or render (when read_chunk is run and the code chunk is available).
Is there a way to spin-off an Rmd (prior to knitting) with
just these chunks populated?
This function
rmarkdown::render("report.Rmd", clean = FALSE)
almost gets there as it leaves the markdown files behind whilst removing extraction and populating chunk_from_myscript however as these files are straight markdown, the chunks are no longer executable and the chunk options are missing. It obviously also doesn't include chunks where eval=TRUE, echo=FALSE which would be needed to run the resulting notebook.
I've also looked at knitr::spin however this would mean disseminating the contents of the report to every source file and isn't terribly ideal.
Reprex
report.Rmd
---
title: 'Report'
---
```{r read_chunks, include=FALSE, cache=FALSE}
knitr::read_chunk("myscript.R")
```
Some documentation
```{r chunk_from_myscript}
```
Some more documentation
```{r chunk_two_from_myscript, eval=TRUE, echo=FALSE}
```
myscript.R
#' # MyScript
#'
#' This is a valid R source file which is formatted
#' using the `knitr::spin` style comments and code
#' chunks.
#' The file's code can be used in large .Rmd reports by
#' extracting the various chunks using `knitr::read_chunk` or
#' it can be spun into its own small commented .Rmd report
#' using `knitr::spin`
# ---- chunk_from_myscript
sessionInfo()
#' This is the second chunk
# ---- chunk_two_from_myscript
1 + 1
Desired Output
notebook.Rmd
---
title: 'Report'
---
Some documentation
```{r chunk_from_myscript}
sessionInfo()
```
Some more documentation
```{r chunk_two_from_myscript, eval=TRUE, echo=FALSE}
1 + 1
```
Working through your reprex I now better understand the issue you are trying to solve. You can knit into an output.Rmd to merge your report and scripts into a single markdown file.
Instead of using knitr::read_chunk, I've read in with knitr::spin to cat the asis output into another .Rmd file. Also note the params$final flag to allow rendering the final document when set as TRUE or allowing the knit to an intermediate .Rmd as FALSE by default.
report.Rmd
---
title: "Report"
params:
final: false
---
```{r load_chunk, include=FALSE}
chunk <- knitr::spin(text = readLines("myscript.R"), report = FALSE, knit = params$final)
```
Some documentation
```{r print_chunk, results='asis', echo=FALSE}
cat(chunk, sep = "\n")
```
to produce the intermediate file:
rmarkdown::render("report.Rmd", "output.Rmd")
output.Rmd
---
title: "Report"
---
Some documentation
```{r chunk_from_myscript, echo=TRUE}
sessionInfo()
```
With the secondary output.Rmd, you could continue with my original response below to render to html_notebook so that the document may be shared without needing to regenerate but still containing the source R markdown file.
To render the final document from report.Rmd you can use:
rmarkdown::render("report.Rmd", params = list(final = TRUE))
Original response
You need to include additional arguments to your render statement.
rmarkdown::render(
input = "output.Rmd",
output_format = "html_notebook",
output_file = "output.nb.html"
)
When you open the .nb.html file in RStudio the embedded .Rmd will be viewable in the editing pane.
Since neither knitr::knit nor rmarkdown::render seem suited to rendering to R markdown, I've managed to somewhat work around this by dynamically inserting the chunk text into each empty chunk and writing that to a new file:
library(magrittr)
library(stringr)
# Find the line numbers of every empty code chunk
get_empty_chunk_line_nums <- function(file_text){
# Create an Nx2 matrix where the rows correspond
# to code chunks and the columns are start/end line nums
mat <- file_text %>%
grep(pattern = "^```") %>%
matrix(ncol = 2, byrow = TRUE)
# Return the chunk line numbers where the end line number
# immediately follows the starting line (ie. chunk is empty)
empty_chunks <- mat[,1] + 1 == mat[,2]
mat[empty_chunks, 1]
}
# Substitute each empty code chunk with the code from `read_chunk`
replace_chunk_code <- function(this_chunk_num) {
this_chunk <- file_text[this_chunk_num]
# Extract the chunk alias
chunk_name <- stringr::str_match(this_chunk, "^```\\{\\w+ (\\w+)")[2]
# Replace the closing "```" with "<chunk code>\n```"
chunk_code <- paste0(knitr:::knit_code$get(chunk_name), collapse = "\n")
file_text[this_chunk_num + 1] %<>% {paste(chunk_code, ., sep = "\n")}
file_text
}
render_to_rmd <- function(input_file, output_file, source_files) {
lapply(source_files, knitr::read_chunk)
file_text <- readLines(input_file)
empty_chunks <- get_empty_chunk_line_nums(file_text)
for (chunk_num in empty_chunks){
file_text <- replace_chunk_code(file_text, chunk_num)
}
writeLines(file_text, output_file)
}
source_files <- c("myscript.R")
render_to_rmd("report.Rmd", "output.Rmd", source_files)
This has the added benefits of preserving chunk options and working
with Python and SQL chunks too since there is no requirement to evaluate
any chunks in this step.

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