Plotting

library(openaq)

The openaq package provides convenience functions to help plot data extending the base::plot function.

To visualize locations on a map, call the plot function after returning a data frame from the list_locations function call. A basic basemap with national boundaries is included based on the Natural Earth dataset via the maps package. If maps is not installed, only the data points will be plotted. Install it with install.packages("maps") to include the world boundary overlay.

locations <- list_locations(
  bbox = c(xmin = 6.291990, ymin = 32.823129, xmax = 37.932615, ymax = 45.181129),
  parameters_id = 2,
  limit = 1000
)
plot(locations)

plot of chunk locations-map-plot

We can configure and customize the figure using standard base::plot parameters in this example coloring the points by provider and customizing the type of marker used.

plot(locations, col = locations$providers_id, pch = 20)

Plot of locations, styled with color by providers_id

The list_sensor_measurements provides a base::plot function to visualize the measurement values as a time series line chart.

measurements <- list_sensor_measurements(
  3920,
  datetime_from = as.POSIXct("2025-01-01 00:00", tz = "America/Denver"),
  datetime_to = as.POSIXct("2025-01-15 23:00", tz = "America/Denver"),
)
plot(measurements)

Line chart of sensor measurements