Matthew Henderson MHenderson

Using arbitrary Leaflet JS plugins with Leaflet for R

The Leaflet JS mapping library has lots of plugins available. The Leaflet package for R provides direct support for some, but far from all, of these plugins, by providing R functions for invoking the plugins.

If you as an R user find yourself wanting to use a Leaflet plugin that isn't directly supported in the R package, you can use the technique shown here to load the plugin yourself and invoke it using JS code.

Built with blockbuilder.org

Nesting and summarizing data is a very common task for data analysis. I thought it would be nice to view parallel ways of nesting and summarizing with both

R | tidyr and dplyr
JavaScript | d3.js ...v4 for fun

To avoid context switching, I'll take advantage of the R package V8. If you are an R user, then these d3.js gists might be helpful d3 nest examples and Mister Nester.

Common Options

-#, --progress-bar Make curl display a simple progress bar instead of the more informational standard meter.

-b, --cookie <name=data> Supply cookie with request. If no =, then specifies the cookie file to use (see -c).

-c, --cookie-jar <file name> File to save response cookies to.

Pushing to Multiple Git Repos

If a project has to have multiple git repos (e.g. Bitbucket and Github) then it's better that they remain in sync.

Usually this would involve pushing each branch to each repo in turn, but actually Git allows pushing to multiple repos in one go.

If in doubt about what git is doing when you run these commands, just

Vim+Zathura+Synctex

In a script called 'vimura':

#!/bin/sh
echo $1
zathura -s -x "gvim --servername $1 -c \"let g:syncpdf='$1'\" --remote +%{line} %{input}" $*

	# originally from: http://stackoverflow.com/questions/42528400/plot-brushing-or-accessing-drawn-shape-geometry-for-spatial-subsets-in-shiny-lea
	# uses https://github.com/bhaskarvk/leaflet.extras

	library(shiny)
	library(leaflet)
	library(leaflet.extras)
	library(sp)

	cities <- structure(list(AccentCity = c("Saint Petersburg", "Harare", "Qingdao",
	"Addis Abeba", "Xian", "Anshan", "Rongcheng", "Kinshasa", "New York",

	#' Tests whether a raw httr response or character vector has a byte order mark (BOM)
	#'
	#' \href{https://en.wikipedia.org/wiki/Byte_order_mark}{What is a byte order mark?}
	#'
	#' @param resp \code{httr} response object or a character vector
	#' @param encoding can be one of \code{UTF-8}, \code{UTF-16} or \code{UTF-16BE}.
	#' Although a BOM could be used with UTF-32 and other encodings, such
	#' encodings are rarely used for data transmission and the three supported
	#' encodings are the most likely ones folks in R will be working with from
	#' web APIs.\cr\cr



	# get recent changes from wikipedia
	library(rvest)
	n_changes <- 5000
	recent_changes_url <- paste0("https://en.wikipedia.org/w/index.php?title=Special:RecentChanges&limit=", n_changes , "&days=1")

	# connect to website
	html <- read_html(recent_changes_url)