Create example hourly pollutant grids

Creates a regular spatial grid over a user-defined bounding box and exports 24 hourly shapefiles. Each grid cell is assigned a random value, making this function useful for generating example datasets and testing workflows.

Usage

make_grid(ymin, ymax, xmin, xmax, pixelSize, dir, date, values = NULL)

Arguments

ymin

Numeric. Minimum latitude of the grid extent.

ymax

Numeric. Maximum latitude of the grid extent.

xmin

Numeric. Minimum longitude of the grid extent.

xmax

Numeric. Maximum longitude of the grid extent.

pixelSize

Numeric. Grid cell size in meters.

dir

Character. Directory where the shapefiles will be written.

date

Character. Date used in the output filenames ("YYYY-mm-dd").

values

Optional. Currently unused.

Value

This function is called for its side effect of writing shapefiles to disk. No value is returned.

Details

The function creates one shapefile for each hour of the day. Pollutant values are generated randomly and are intended only for examples and testing.

Examples

if (FALSE) { # \dontrun{
make_grid(
  ymin = -31.6,
  ymax = -31.3,
  xmin = -64.3,
  xmax = -64.0,
  pixelSize = 1000,
  dir = "example_grids/",
  date = "2019-08-01"
)
} # }