Create an agricultural analysis project

Builds the object every other function in the package operates on. The unit of observation is a management unit within a season: a field, plot or administrative area, together with the window over which the crop grew. Each observation is keyed by (unit_id, season_id), and every covariate layer added later must reduce to that key.

Usage

agri_project(
  data,
  unit_id = NULL,
  x = NULL,
  y = NULL,
  season = NULL,
  start = NULL,
  end = NULL,
  crop = NULL,
  crs = 4326,
  cache_dir = NULL
)

Arguments

data

A data frame with one row per management unit and season.

unit_id, x, y

Column names giving the unit identifier and its coordinates. Detected from names such as unit_id, field, lon, lat when NULL.

season

Column naming the season, typically a year. Detected from season or year.

start, end

Columns giving the start and end of the growing window as dates. Detected from names such as planting/sowing and harvest.

crop

Column giving the crop, if more than one is present.

crs

Coordinate reference system as an EPSG code. Only 4326 is currently treated as geographic; anything else is taken as projected, which changes how distances are computed.

cache_dir

Directory for cached downloads. Defaults to a session temporary directory, so nothing is written outside it unless asked.

Value

An object of class agri_project.

Details

Column roles are detected from common names when not given explicitly, so agri_project(data) usually works unchanged. Detection is reported by the print method, and can always be overridden.

See also

add_climate(), build_features(), check_project()

Examples

d <- demo_agri_data(n_units = 6, n_seasons = 2)
p <- agri_project(d)
p
#> <agri_project>
#>   observations : 12 
#>   units        : 6 (unit_id) 
#>   seasons      : 2 (season) 
#>   window       : 2018-04-30 to 2019-10-20 
#>   extent       : x [-95.000, -88.000]  y [39.000, 41.500] 
#>   layers       : none 
#>   windows      : not derived 
#>   features     : not built