Add polar markers to leaflet map

This function is similar (but not identical to) the leaflet::addMarkers() and leaflet::addCircleMarkers() functions in leaflet, which allows users to add openair directional analysis plots to any leaflet map and have more control over groups and layerIds than in "all-in-one" functions like polarMap().

Usage

addPolarMarkers(
  map,
  pollutant,
  fun = openair::polarPlot,
  lng = NULL,
  lat = NULL,
  layerId = NULL,
  group = NULL,
  popup = NULL,
  popupOptions = NULL,
  label = NULL,
  labelOptions = NULL,
  options = leaflet::markerOptions(),
  clusterOptions = NULL,
  clusterId = NULL,
  key = FALSE,
  d.icon = 200,
  d.fig = 3.5,
  data = leaflet::getMapData(map),
  ...
)

addPolarDiffMarkers(
  map,
  pollutant,
  before = leaflet::getMapData(map),
  after = leaflet::getMapData(map),
  lng = NULL,
  lat = NULL,
  layerId = NULL,
  group = NULL,
  popup = NULL,
  popupOptions = NULL,
  label = NULL,
  labelOptions = NULL,
  options = leaflet::markerOptions(),
  clusterOptions = NULL,
  clusterId = NULL,
  key = FALSE,
  d.icon = 200,
  d.fig = 3.5,
  ...
)

Arguments

map

a map widget object created from leaflet()

pollutant

The name of the pollutant to be plot. Note that, if fun = openair::windRose, you must set pollutant = "ws".

fun

An openair directional analysis plotting function. Supported functions include openair::polarPlot() (the default), openair::polarAnnulus(), openair::polarFreq(), openair::percentileRose(), openair::pollutionRose() and openair::windRose(). For openair::polarDiff(), use addPolarDiffMarkers().

lng

The decimal longitude.

lat

The decimal latitude.

layerId

the layer id

group

the name of the group the newly created layers should belong to (for clearGroup() and addLayersControl() purposes). Human-friendly group names are permitted–they need not be short, identifier-style names. Any number of layers and even different types of layers (e.g., markers and polygons) can share the same group name.

popup

A column of data to be used as a popup.

popupOptions

A Vector of popupOptions() to provide popups

label

A column of data to be used as a label.

labelOptions

A Vector of labelOptions() to provide label options for each label. Default NULL

options

a list of extra options for tile layers, popups, paths (circles, rectangles, polygons, ...), or other map elements

clusterOptions

if not NULL, markers will be clustered using Leaflet.markercluster; you can use markerClusterOptions() to specify marker cluster options

clusterId

the id for the marker cluster layer

key

Should a key for each marker be drawn? Default is FALSE.

d.icon

The diameter of the plot on the map in pixels. This will affect the size of the individual polar markers. Alternatively, a vector in the form c(width, height) can be provided if a non-circular marker is desired.

d.fig

The diameter of the plots to be produced using openair in inches. This will affect the resolution of the markers on the map. Alternatively, a vector in the form c(width, height) can be provided if a non-circular marker is desired.

data

A data frame. The data frame must contain the data to plot your choice of openair directional analysis plot, which includes wind speed (ws), wind direction (wd), and the column representing the concentration of a pollutant. In addition, data must include a decimal latitude and longitude. By default, it is the data object provided to leaflet::leaflet() initially, but can be overridden.

...

Other arguments for the plotting function (e.g. period for openair::polarAnnulus()).

before, after

A data frame that represents the before/after case. See openair::polarPlot() for details of different input requirements. By default, both before and after are the data object provided to leaflet::leaflet() initially, but at least one should be overridden.

Value

A leaflet object.

Functions

• addPolarMarkers(): Add any one-table polar marker (e.g., openair::polarPlot())

• addPolarDiffMarkers(): Add the two-table openair::polarDiff() marker.

See also

shiny::runExample(package = "openairmaps") to see examples of this function used in a shiny::shinyApp()

Examples

if (FALSE) { # \dontrun{
library(leaflet)
library(openair)

# different types of polar plot on one map
leaflet(data = polar_data) |>
  addTiles() |>
  addPolarMarkers(
    "ws",
    fun = openair::windRose,
    annotate = FALSE,
    group = "Wind Rose"
  ) |>
  addPolarMarkers("nox", fun = openair::polarPlot, group = "Polar Plot") |>
  addLayersControl(
    baseGroups = c("Wind Rose", "Polar Plot")
  )

# use of polar diff (NB: both 'before' and 'after' inherit from `leaflet()`,
# so at least one should be overridden - in this case 'after')
leaflet(data = polar_data) |>
  addTiles() |>
  addPolarDiffMarkers("nox",
    after = dplyr::mutate(polar_data, nox = jitter(nox, 5))
  )
} # }