Smooth a potentiometric surface raster — ps_smooth

Applies a focal moving-window smoother to a potentiometric surface raster. This can be useful when an interpolated surface is technically valid but too locally rough for contour development or hydraulic-gradient visualization.

Usage

ps_smooth_surface(
  surface,
  window_size = 3,
  method = c("mean", "median"),
  weights = NULL,
  iterations = 1,
  na.rm = TRUE,
  preserve_na = TRUE,
  filename = "",
  overwrite = FALSE
)

Arguments

surface: A terra::SpatRaster potentiometric surface.
window_size: Odd integer window size used when weights is NULL.
method: Smoothing statistic. Supported values are "mean" and "median".
weights: Optional odd-dimension numeric matrix of focal weights. NA values in the matrix are ignored by terra::focal().
iterations: Number of smoothing passes.
na.rm: Ignore missing values inside the focal window.
preserve_na: Preserve the original NA footprint after smoothing.
filename: Optional output raster filename.
overwrite: Overwrite filename when it exists.

Value

A smoothed terra::SpatRaster.

Examples

data("synthetic_wells")
pts <- ps_make_points(synthetic_wells, "x", "y", "gw_elevation",
                      "well_id", "EPSG:26916")
s <- ps_interpolate(pts, grid_res = 100)
#> Warning: TPS GCV selected lambda 1.81248e-05 at a search boundary; inspect sensitivity and prediction support.
smoothed <- ps_smooth_surface(s$TPS, window_size = 5)
smoothed
#> class       : SpatRaster
#> size        : 30, 31, 1  (nrow, ncol, nlyr)
#> resolution  : 100, 100  (x, y)
#> extent      : 500193.2, 503293.2, 4640010, 4643010  (xmin, xmax, ymin, ymax)
#> coord. ref. : NAD83 / UTM zone 16N (EPSG:26916)
#> source(s)   : memory
#> name        :        TPS
#> min value   : 163.675095
#> max value   : 172.806939