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Extract grid points within a specific county boundary

Source: R/get_grid_points.R
get_grid_points.Rd

Extract spatial grid points from a gridded SpatRaster object that fall within the boundary of a specified county. Output can be limited to points strictly within the boundary or include all masked points overlapping the boundary extent.

Usage

get_grid_points(
  gridded_data,
  sf_county,
  county_name,
  output = c("within", "masked")
)

Arguments

gridded_data

A SpatRaster object containing gridded time series data (e.g., temperature).

sf_county

A sf object containing county boundary. For Virginia, the sf_va_county dataset provided in this package may be used.

county_name

Character string. Name of the county or independent city to extract. Must match an entry in the county column of sf_county.

output

Character string indicating the type of output. "within" (default) returns only grid points strictly within the boundary, "masked" returns all points from the masked raster (may include edge pixels).

Value

  • output = "within": A tibble of grid points strictly within the specified boundary.

  • output = "masked": A sf object of all points from the masked raster (may include edge pixels).

Examples

library(sf)
#> Linking to GEOS 3.12.1, GDAL 3.8.4, PROJ 9.4.0; sf_use_s2() is TRUE

richmond_msa <- load_era5_temperature()
va_county <- sf_va_county

masked_output <- get_grid_points(gridded_data = richmond_msa,
                                 sf_county = va_county,
                                 county_name = "Amelia County",
                                 output = "masked")
#> Warning: Expected 2 pieces. Missing pieces filled with `NA` in 45 rows [21, 45, 69, 93,
#> 117, 141, 165, 189, 213, 237, 261, 285, 309, 333, 357, 381, 405, 429, 453, 477,
#> ...].
#> Warning: Using one column matrices in `filter()` was deprecated in dplyr 1.1.0.
#> ℹ Please use one dimensional logical vectors instead.
#> ℹ The deprecated feature was likely used in the chva.extras package.
#>   Please report the issue at <https://github.com/le-huynh/chva.extras/issues>.

within_output <- get_grid_points(gridded_data = richmond_msa,
                                 sf_county = va_county,
                                 county_name = "Amelia County",
                                 output = "within")
#> Warning: Expected 2 pieces. Missing pieces filled with `NA` in 45 rows [21, 45, 69, 93,
#> 117, 141, 165, 189, 213, 237, 261, 285, 309, 333, 357, 381, 405, 429, 453, 477,
#> ...].