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Calculate elevation covariates

Source: R/calculate_covariates.R
calculate_gmted.Rd

Extract elevation values at point locations. Returns a data.frame object containing locs_id, year of release, and elevation variable. Elevation variable column name reflects the elevation statistic, spatial resolution of from, and circular buffer radius (ie. Breakline Emphasis at 7.5 arc-second resolution with 0 meter buffer: breakline_emphasis_r75_0).

Usage

calculate_gmted(
  from,
  locs,
  locs_id = NULL,
  radius = 0,
  fun = "mean",
  geom = FALSE,
  ...
)

Arguments

from

SpatRaster(1). Output from process_gmted().

locs

data.frame. character to file path, SpatVector, or sf object.

locs_id

character(1). Column within locations CSV file containing identifier for each unique coordinate location.

radius

integer(1). Circular buffer distance around site locations. (Default = 0).

fun

character(1). Function used to summarize multiple raster cells within sites location buffer (Default = mean).

geom

FALSE/"sf"/"terra".. Should the function return with geometry? Default is FALSE, options with geometry are "sf" or "terra". The coordinate reference system of the sf or SpatVector is that of from.

...

Placeholders

Value

a data.frame or SpatVector object

See also

process_gmted()

Author

Mitchell Manware

Examples

## NOTE: Example is wrapped in `\dontrun{}` as function requires a large
##       amount of data which is not included in the package.
if (FALSE) { # \dontrun{
loc <- data.frame(id = "001", lon = -78.90, lat = 35.97)
calculate_gmted(
  from = gmted, # derived from process_gmted() example
  locs = loc,
  locs_id = "id",
  radius = 0,
  fun = "mean",
  geom = FALSE
)
} # }