restrict_to_country {SeaVal}

restricts data to a specified country

Description

Restricts a dataset to one or more countries, specified by their names. If you have lon/lat data and don't know which countries these coordinates belong to, see add_country_names. Can restrict data to a rectangle around a given country as well (usually looks nicer for plotting).

Usage

restrict_to_country(dt, ct, rectangle = FALSE, tol = 1)

Arguments

dt

the data table.

ct

name of the country, or vector containing multiple country names

rectangle

logical. If FALSE (default), the data is restricted to the gridcells for which the centerpoint lies within the selected country (e.g. for computing mean scores for a country). If TRUE, the data is kept for a rectangle containing the entire country, therefore also containing gridpoints outside the country. This is the preferred option for plotting data for a specific country.

tol

Only used when rectangle == TRUE. A tolerance value for widening the plotting window, making things look a bit nicer.

Value

the data table, restricted to the selected country

Examples

# example data:
ex_dt = chirps_monthly[lat < 0 & month == 11 & year == 2020]
dt = restrict_to_country(ex_dt,'Kenya')