gail_shp: Geo-Assignment of Irregular Locations to Shapes

In jelsema/GAIL: Geo-Assigment of Irregular Locations

Description

Allocates the number of cases/events from irregular spatial units onto to regular set of spatial units. The regular spatial units are assumed to have POLYGON geometry, while the irregular spatial units are assumed to have POINT geometry.

Note that this function is largely a wrapper for using sf::st_contains with basic aggregation before and after. It is provided primarily for (relative) consistency with gail.

Usage

gail_shp(sp_units, cases, suid, num_cases, group, label, convert = FALSE,
  ...)

Arguments

sp_units	Dataset of regular spatial units, see details.
cases	Dataset containing the the cases, see details.
suid	Column name in both sp_units and cases which contains the spatial unit identification / name.
num_cases	Column name from cases containing the number of cases, see details.
group	Optional name of variable in cases to use for filtering. See details.
label	Optional value of group by which to filter. See details.
convert	Logical, convert returned object to Spatial* type objects (from sp).
...	Space for additional arguments.

Details

• sp_units should be an object of class sf (from the sf package). The argument convert can be used to convert the results into a Spatial* object (from the sp package).

• cases contains the units (and associated number of cases) to be allocated. This should be an object of class sf. If not, it must have coordinates latitude and longitude and will be converted to an sf object. The dataset of cases should be aggregated and have a column for the number of cases. If the column given by num_cases does not exist in cases, then cases will be aggregated by suid to create the column.

• group and label : If provided, these arguments are used to filter cases to rows where group == label.

Value

Returns a copy of sp_units after having added a column named num_cases, which contains the number of cases which fall within the boundry of each spatial unit.

See Also

gail

jelsema/GAIL documentation built on June 29, 2019, 11:48 a.m.