I would like to know if there is any function which makes it easy to visualize an html object in the RStudio's viewer pane. For instance, I would like to know if it would be possible to view an html table in the viewer pane.
library("Quandl")
library("knitr")
df <- Quandl("FBI_UCR/USCRIME_TYPE_VIOLENTCRIMERATE")
kable(head(df[,1:9]), format = 'html', table.attr = "class=nofluid")
I have a solution that works for kable tables.
kable(iris) %>% kableExtra::kable_styling()
This is automatically displayed in the viewer pane. No need for tempfile.
I have this functionality in my htmlTable package and the function is rather simple:
print.htmlTable<- function(x, useViewer = TRUE, ...){
# Don't use viewer if in knitr
if (useViewer &&
!"package:knitr" %in% search()){
htmlFile <- tempfile(fileext=".html")
htmlPage <- paste("<html>",
"<head>",
"<meta http-equiv=\"Content-type\" content=\"text/html;charset=UTF-8\">",
"</head>",
"<body>",
"<div style=\"margin: 0 auto; display: table; margin-top: 1em;\">",
x,
"</div>",
"</body>",
"</html>", sep="\n")
cat(htmlPage, file=htmlFile)
viewer <- getOption("viewer")
if (!is.null(viewer) &&
is.function(viewer)){
# (code to write some content to the file)
viewer(htmlFile)
}else{
utils::browseURL(htmlFile)
}
}else{
cat(x)
}
}
RStudio recommends that you use the getOption("viewer") instead of #Ramnath's suggestion, the raw RStudio::viewer(). My solution also adds the utils::browserURL() in case you are not using RStudio. I got the idea from this blog post.
Here is a quick way to do this in RStudio
view_kable <- function(x, ...){
tab <- paste(capture.output(kable(x, ...)), collapse = '\n')
tf <- tempfile(fileext = ".html")
writeLines(tab, tf)
rstudio::viewer(tf)
}
view_kable(head(df[,1:9]), format = 'html', table.attr = "class=nofluid")
If the kable function can return an object of class kable, then one could rename view_kable as print.kable in which case merely calling the kable function would open the table in the viewer. If you think this is useful, please go ahead and file a feature request on the knitr github page.
As was explained on this RStudio Support page, the key is to use tempfile() :
Note that the Viewer pane can only be used for local web content. This
content can either be static HTML files written to the session
temporary directory (i.e. files with paths generated by the tempfile
function) or a locally run web application.
See my answer to this question for a bare-bones example.
For kable objects, we can use print.kableExtra
library(knitr)
x <- kable(head(iris), format = "html")
library(kableExtra)
class(x) <- c("kableExtra", class(x))
print(x)
Related
The pillar package offers a number of options to format tibble printing.
https://pillar.r-lib.org/reference/pillar-package.html#package-options
For example, this is what I see on my Windows machine, which supports these options:
But when I set the same options for rmarkdown document, I don't see any difference in the printed output.
Is there a way to successfully get this to work or this is not supported in rmarkdown itself?
In the vignette for the tibble package, there is a possible solution. In your setup chunk of your .Rmd file, put:
knitr::opts_chunk$set(collapse = TRUE, comment = "#>")
library(tibble)
set.seed(1014)
options(crayon.enabled = TRUE)
options(pillar.bold = TRUE, pillar.subtle_num = TRUE)
knitr::opts_chunk$set(collapse = TRUE, comment = pillar::style_subtle("#>"))
colourise_chunk <- function(type) {
function(x, options) {
lines <- x
if (type != "output") {
lines <- crayon::red(lines)
}
paste0(
'<div class="sourceCode"><pre class="sourceCode"><code class="sourceCode">',
paste0(
fansi::sgr_to_html(htmltools::htmlEscape(lines)),
collapse = "\n"
),
"</code></pre></div>"
)
}
}
knitr::knit_hooks$set(
output = colourise_chunk("output"),
message = colourise_chunk("message"),
warning = colourise_chunk("warning"),
error = colourise_chunk("error")
)
In a new chunk:
broom::tidy(stats::chisq.test(table(ggplot2::msleep$vore)))
My HTML output:
I'd say that from my markdown experience that Pillow will not work as markdown uses pandoc.
As alternatives, I'd recommend using the kable package for a similar look using it's themes options. A handy tutorial with using a relatively similar theme ->
https://cran.r-project.org/web/packages/kableExtra/vignettes/awesome_table_in_html.html
Another cool option of making really cool markdown tables would be to use formattable, which has a lot of in-depth options for formatting
And a couple of handy tutorials for that ->
https://www.littlemissdata.com/blog/prettytables
https://www.littlemissdata.com/blog/pretty-r-tables-in-github
Hopefully, this helps you out.
I am working with a function that outputs an svg object. As I see the SVG object is essentially a string of characters.
I was wondering how to
1) plot the svg output from the function
2) save this svg object to disk under an svg extension? I tried ggsave but just resulted in an error.
I am fairly new to svg handling, so would appreciate any inputs.
Thanks!
1) I tried that for a package I was developing and it was not straightforward. In the end, I needed two libraries: rsvg and grImport2. Here is the code I used:
tfile <- tempfile(fileext = ".svg")
tfile2 <- tempfile(fileext = ".png")
cat(svg_code, file=tfile)
if (requireNamespace("rsvg", quietly = TRUE) && requireNamespace("grImport2", quietly = TRUE)) {
rsvg::rsvg_svg(svg = tfile, tfile2)
p <- grImport2::readPicture(tfile2)
grImport2::grid.picture(p)
} else {
if (systemShow == FALSE && outFile == ''){
warning("The figure cannot be rendered in the plot window. Please, use the arguments outFile and/or systemShow.")
}
}
if (systemShow){
utils::browseURL(tfile)
}
The first conditional is in case the system does not allow the installation of either package. As you can see, you first need to write the svg code (svg_code) to a file, in this case temporary (tfile). Then, rsvg_svg writes a temporary png file (tfile2). Finally, grImport2::readPicture and grImport2::grid.picture show the converted file in the plot window. I also left the part where the user can set a boolean variable (systemShow) and the package will attempt to open the file on the default system svg viewer.
2) That one is much easier. You just need to write the code to a file as text, like cat(svg_code, file='path_to_file.svg').
So I'm trying to write an html R markdown document with interactive shiny bits that allow the user to edit a graph and then download the results to a pdf. However, there is something catastrophically wrong with the way that I'm trying to do this because as soon as the html starts, it overwrites the original markdown file with the contents of the pdf - turning it into complete gibberish right in the editor.
I doubt that I've found a completely new way to fail at R but I haven't been able to find where anybody else has had this issue. Additionally, I've looked over the shiny reference material and I'm just going in circles at this point, so any help would be greatly appreciated.
I'm using Rstudio 1.0.44, rmarkdown 1.2 and shiny 0.14.2. A small (not)working example:
---
title: "Minimum Failing Example"
author: "wittyalias"
date: "December 5, 2016"
output: html_document
runtime: shiny
---
```{r echo = FALSE}
library(ggplot2)
today <- Sys.Date()
inputPanel(downloadButton("dnld", label = "Download pdf"))
renderPlot({
# Example code from http://www.cookbook-r.com/Graphs/Multiple_graphs_on_one_page_(ggplot2)/
p1 <<- ggplot(ChickWeight, aes(x=Time, y=weight, colour=Diet, group=Chick)) +
geom_line() +
ggtitle("Growth curve for individual chicks")
p1
})
reactive({
fname <- paste0("Chick Weight - ", today, ".pdf")
output$dnld <- downloadHandler(filename = fname,
content = makethepdf(file))
makethepdf <- function(fname) {
pdf(fname,
width = 14,
height = 8.5)
p1
dev.off()
}
})
```
EDIT: To be clear: I want the user to be able to download multiple pages of graphs, some of which will have different formatting. The user won't be downloading just a pdf version of the markdown document.
This happens because reasons I weren't able to identify makethepdf runs with the file = [name of the file]. Insert a print(fname) to see. The download handler isn't supposed to be inside an observer though. You need to have it outside on its own. I also failed to make pdf() dev.off() combination work for some reason so here's a working version below.
output$dnld = downloadHandler(filename = paste0("Chick Weight - ", today, ".pdf"),
content = function(file){
ggsave(file, plot = p1, width = 14, height = 8.5)
})
Use tempfile() and tempdir() to create a temporary file:
output$downloadReport = downloadHandler(
filename = function() {
normalizePath(tempfile("report_", fileext = ".docx"), winslash = "/")
},
content = function(file) {
out = rmarkdown::render("./report.Rmd",
output_file = file,
output_dir = tempdir(),
output_format = "pdf_document",
intermediates_dir = tempdir(),
envir = new.env(),
params = list( fontSize = 10)
)
})
I usually use a separate .Rmd template for my downloaded reports as the layout and text are usually similar but not identical to what works in an app.
I also find using parameters is a convenient way to pass input settings from my app to my report. See this RStudio post for details
Alright, so there are a number of problems with my code, but using some of the suggestions in the other answers I've been able to work it out.
The primary problem with this little document is that content in the downloadHandler is a function, but in my code I set content equal to the result of a function call. It looks like when the shiny app is first run it compiles content, thinking that it is a function, but actually ends up calling the function. It sends file as an arguement, which doesn't seem to exist except as a base function. Calling makethepdf with just file throws an error when I use it in the console, but for whatever reason in this app it just goes with the call, apparently with file = [name of the .Rmd] (just as OganM said).
To fix, change this:
output$dnld <- downloadHandler(filename = fname,
content = makethepdf(file))
to
output$dnld <- downloadHandler(filename = fname,
content = makethepdf)
To be clear: this code does not overwrite the .Rmd file if content calls makethepdf with any argument other than file. For instance, content = makethepdf(fnm)) causes the download button to display an object not found error and content = makethepdf(fname)) causes the download button to throw an attempt to apply non-function error when pressed.
I have been using rmarkdown/knitr's knit to html capability to generate html code for some blogs. I've found it extremely helpful and convenient, but have been running into some problems lately with file size.
When I knit a script that has graphics that use shapefiles or ggmap images, the html file gets too big for the blog host to make sense of it (I've tried with both blogger and wordpress). I believe this has to do with the relatively large data.frames/files that are the shapefiles/ggmap being put into html form. Is there anything I can do to get a smaller html file that can be parsed by a blog host?
For reference, the html output from an rmarkdown script with one graphic using a ggmap layer, a layer of shapefiles and some data is 1.90MB, which is too big for blogger or wordpress to handle in html input. Thanks for any ideas.
Below are 3 different options to help you reduce the file size of HTML files with encoded images.
1. Optimize an existing HTML file
You can run this Python script on an existing HTML file. The script will:
decode the base64 encoded images
run pngquant to optimize the images
re-encode the optimized images as base64
Usage:
python optimize_html.py infile.html
It writes output to infile-optimized.html.
2. Use the built-in knitr hook for optimizing PNG images
knitr 1.15 includes a hook called hook_optipng that will run the optipng program on generated PNG files to reduce file size.
Here is a .Rmd example (taken from: knitr-examples/035-optipng.Rmd):
# 035-optipng.Rmd
This demo shows you how to optimize PNG images with `optipng`.
```{r setup}
library(knitr)
knit_hooks$set(optipng = hook_optipng)
```
Now we set the chunk option `optipng` to a non-`NULL` value,
e.g. `optipng=''`, to activate the hook. This string is passed to
`optipng`, so you can use `optipng='-o7'` to optimize more heavily.
```{r use-optipng, optipng=''}
library(methods)
library(ggplot2)
set.seed(123)
qplot(rnorm(1e3), rnorm(1e3))
```
3. Write your own knitr hook for any image optimizer
Writing your own hook is also quite easy, so I wrote a hook that calls the pngquant program. I find that pngquant runs faster, and the output files are smaller and look better.
Here is a .R example that defines and uses hook_pngquant (taken from this gist).
#' ---
#' title: "pngquant demo"
#' author: "Kamil Slowikowski"
#' date: "`r Sys.Date()`"
#' output:
#' html_document:
#' self_contained: true
#' ---
#+ setup, include=FALSE
library(knitr)
# Functions taken from knitr/R/utils.R
all_figs = function(options, ext = options$fig.ext, num = options$fig.num) {
fig_path(ext, options, number = seq_len(num))
}
in_dir = function(dir, expr) {
if (!is.null(dir)) {
owd = setwd(dir); on.exit(setwd(owd))
}
wd1 = getwd()
res = expr
wd2 = getwd()
if (wd1 != wd2) warning(
'You changed the working directory to ', wd2, ' (probably via setwd()). ',
'It will be restored to ', wd1, '. See the Note section in ?knitr::knit'
)
res
}
is_windows = function() .Platform$OS.type == 'windows'
in_base_dir = function(expr) {
d = opts_knit$get('base.dir')
if (is.character(d) && !file_test('-d', d)) dir.create(d, recursive = TRUE)
in_dir(d, expr)
}
# Here is the code you can modify to use any image optimizer.
hook_pngquant <- function(before, options, envir) {
if (before)
return()
ext = tolower(options$fig.ext)
if (ext != "png") {
warning("this hook only works with PNG")
return()
}
if (!nzchar(Sys.which("pngquant"))) {
warning("cannot find pngquant; please install and put it in PATH")
return()
}
paths = all_figs(options, ext)
in_base_dir(lapply(paths, function(x) {
message("optimizing ", x)
cmd = paste(
"pngquant",
if (is.character(options$pngquant)) options$pngquant,
shQuote(x)
)
message(cmd)
(if (is_windows())
shell
else system)(cmd)
x_opt = sub("\\.png$", "-fs8.png", x)
file.rename(x_opt, x)
}))
return()
}
# Enable this hook in this R script.
knit_hooks$set(
pngquant = hook_pngquant
)
#' Here we set the chunk option `pngquant='--speed=1 --quality=0-50'`,
#' which activates the hook.
#+ use-pngquant, pngquant='--speed=1 --quality=0-50'
library(methods)
library(ggplot2)
set.seed(123)
qplot(rnorm(1e3), rnorm(1e3))
I prefer to write my reports in R scripts (.R) instead of R markdown documents (.Rmd). See http://yihui.name/knitr/demo/stitch/ for more information on how to do that.
One thing you could do would be to not use embedded image and other resources. To achieve this, you can set the self_contained option in the YAML header for your document to false, e.g.:
---
output:
html_document:
self_contained: false
---
More info here: http://rmarkdown.rstudio.com/html_document_format.html
I would like to include at the end of the R markdown documention the help page about the mtcars dataset.
In my file I included the following:
```{r}
?mtcars
```
When I compile the markdown (output is to PDF - knitr), upon processing this instruction the help page comes up in my browser but the resulting pdf lacks this section.
Is there a way I could acheive this other then copying from one place to the other?
Thank you.
We can adapt Yihui Xie's static_help function to get the html source for a given help file
static_help <- function(pkg, topic, out, links = tools::findHTMLlinks()) {
pkgRdDB = tools:::fetchRdDB(file.path(find.package(pkg), 'help', pkg))
force(links)
tools::Rd2HTML(pkgRdDB[[topic]], out, package = pkg,
Links = links, no_links = is.null(links))
}
If we write the source to a temporary file we can then read it back in and strip off the header and footer, giving you the body of the help file to include in your markdown document
```{r, echo = FALSE, results = "asis"}
static_help <- function(pkg, topic, out, links = tools::findHTMLlinks()) {
pkgRdDB = tools:::fetchRdDB(file.path(find.package(pkg), 'help', pkg))
force(links)
tools::Rd2HTML(pkgRdDB[[topic]], out, package = pkg,
Links = links, no_links = is.null(links))
}
tmp <- tempfile()
static_help("datasets", "mtcars", tmp)
out <- readLines(tmp)
headfoot <- grep("body", out)
cat(out[(headfoot[1] + 1):(headfoot[2] - 1)], sep = "\n")
```
EDIT
The above solution produced HTML output, whereas the question actually asked for PDF output. We can adapt the above to return latex output instead; this time the only-post-editing required is to switch % for \n
```{r, echo = FALSE, results = "asis"}
static_help <- function(pkg, topic, out, links = tools::findHTMLlinks()) {
pkgRdDB = tools:::fetchRdDB(file.path(find.package(pkg), 'help', pkg))
force(links)
tools::Rd2latex(pkgRdDB[[topic]], out, package = pkg,
Links = links, no_links = is.null(links))
}
tmp <- tempfile()
static_help("datasets", "mtcars", tmp)
out <- readLines(tmp)
out <- gsub("%", "\n", out, fixed = TRUE)
cat(out, sep = "\n")
```
However the .Rd files depend on Rd.sty. The simplest way to get LaTeX to find Rd.sty is to put a copy in the same directory as your .Rmd file. Then you need to define a custom template to replace the default pandoc LaTeX template. Again, the simplest solution is to put a copy of the default template in the same directory as your .Rmd file, then modify it by replacing everything between the \documentclass command and the \begin{document} command (lines 2 - 145) with the command
\usepackage{Rd}
Finally modify the metadata of your .Rmd file to use the new template
---
output:
pdf_document:
template: template.tex
---