Pollution rose plots on interactive leaflet maps

pollroseMap() creates a leaflet map using "pollution roses" as markers. Any number of pollutants can be specified using the pollutant argument, and multiple layers of markers can be added and toggled between using control.

Usage

pollroseMap(
  data,
  pollutant = NULL,
  statistic = "prop.count",
  breaks = NULL,
  latitude = NULL,
  longitude = NULL,
  control = NULL,
  popup = NULL,
  label = NULL,
  provider = "OpenStreetMap",
  cols = "turbo",
  alpha = 1,
  key = FALSE,
  draw.legend = TRUE,
  collapse.control = FALSE,
  d.icon = 200,
  d.fig = 3.5,
  type = deprecated(),
  ...
)

Arguments

data

A data frame. The data frame must contain the data to plot the directional analysis marker, 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.

pollutant

The column name(s) of the pollutant(s) to plot. If multiple pollutants are specified, they can be toggled between using a "layer control" interface.

statistic

The statistic to be applied to each data bin in the plot. Options currently include "prop.count", "prop.mean" and "abs.count". The default "prop.count" sizes bins according to the proportion of the frequency of measurements. Similarly, "prop.mean" sizes bins according to their relative contribution to the mean. "abs.count" provides the absolute count of measurements in each bin.

breaks

Most commonly, the number of break points. If not specified, each marker will independently break its supplied data at approximately 6 sensible break points. When breaks are specified, all markers will use the same break points. Breaks can also be used to set specific break points. For example, the argument breaks = c(0, 1, 10, 100) breaks the data into segments <1, 1-10, 10-100, >100.

latitude, longitude

The decimal latitude/longitude. If not provided, will be automatically inferred from data by looking for a column named "lat"/"latitude" or "lon"/"lng"/"long"/"longitude" (case-insensitively).

control

Used for splitting the input data into different groups which can be selected between using a "layer control" interface, passed to the type argument of openair::cutData(). control cannot be used if multiple pollutant columns have been provided.

popup

Columns to be used as the HTML content for marker popups. Popups may be useful to show information about the individual sites (e.g., site names, codes, types, etc.). If a vector of column names are provided they are passed to buildPopup() using its default values.

label

Column to be used as the HTML content for hover-over labels. Labels are useful for the same reasons as popups, though are typically shorter.

provider

The base map(s) to be used. See http://leaflet-extras.github.io/leaflet-providers/preview/ for a list of all base maps that can be used. If multiple base maps are provided, they can be toggled between using a "layer control" interface. By default, the interface will use the provider names as labels, but users can define their own using a named vector (e.g., c("Default" = "OpenStreetMap", "Satellite" = "Esri.WorldImagery"))

cols

The colours used for plotting. See openair::openColours() for more information.

alpha

The alpha transparency to use for the plotting surface (a value between 0 and 1 with zero being fully transparent and 1 fully opaque).

key

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

draw.legend

When breaks are specified, should a shared legend be created at the side of the map? Default is TRUE.

collapse.control

Should the "layer control" interface be collapsed? Defaults to 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.

type

. Different sites are now automatically detected based on latitude and longitude. Please use label and/or popup to label different sites.

...

Arguments passed on to openair::pollutionRose

key.footer

Adds additional text/labels below the scale key. See key.header for further information.

key.position

Location where the scale key is to plotted. Allowed arguments currently include “top”, “right”, “bottom” and “left”.

paddle

Either TRUE or FALSE. If TRUE plots rose using 'paddle' style spokes. If FALSE plots rose using 'wedge' style spokes.

seg

When paddle = TRUE, seg determines with width of the segments. For example, seg = 0.5 will produce segments 0.5 * angle.

normalise

If TRUE each wind direction segment is normalised to equal one. This is useful for showing how the concentrations (or other parameters) contribute to each wind sector when the proportion of time the wind is from that direction is low. A line showing the probability that the wind directions is from a particular wind sector is also shown.

Value

A leaflet object.

See also

the original openair::pollutionRose()

pollroseMapStatic() for the static ggmap equivalent of pollroseMap()

Other interactive directional analysis maps: annulusMap(), diffMap(), freqMap(), percentileMap(), polarMap(), windroseMap()

Examples

if (FALSE) {
pollroseMap(polar_data,
  pollutant = "nox",
  statistic = "prop.count",
  provider = "Stamen.Toner"
)
}