Aggregate sxts over shapefile polygons (zonal statistics)

For each polygon, finds all sxts spatial points that fall within it and aggregates them row-wise (per time step) using FUN. Returns a plain xts with polygon names as column names. Points that do not fall within any polygon are silently dropped.

The polygon source can be supplied in three ways (mutually exclusive):

shapefile — an sf/Spatial* object or a file path; name_col must also be given.
country — a country name matching world_data$name; yields one output column named after the country.
continent — a continent name matching world_data$continent; yields one output column per country within the continent.

Aggregates sxts cells within polygon zones (shapefile, country, or continent), returning a plain xts with one column per zone. Points outside all zones are dropped.

Usage

zonal_stats(x, ...)

# S3 method for class 'sxts'
zonal_stats(
  x,
  shapefile = NULL,
  name_col = NULL,
  country = NA,
  continent = NA,
  FUN = mean,
  ...
)

Arguments

x: An sxts object.
...: Additional arguments forwarded to FUN (e.g. na.rm = TRUE).
shapefile: An sf object, Spatial* object, or file path to a shapefile.
name_col: Character; column in shapefile whose values become output column names.
country: Character; country name (matches world_data$name).
continent: Character; continent name (matches world_data$continent).
FUN: Aggregation function applied row-wise within each polygon (default: mean).

Value

A plain xts with one column per polygon that contains at least one sxts point.