Compare two potentiometric surfaces — ps_compare

Compares compatible surfaces on their common finite support. Alignment is an explicit operation and defaults to an error. The signed default is surface B minus surface A; percentage head change is not calculated.

Usage

ps_compare_surfaces(
  surface_a,
  surface_b,
  direction = c("b_minus_a", "a_minus_b"),
  align = c("error", "to_a", "to_b", "template"),
  template = NULL,
  resampling = c("bilinear", "near"),
  contour_levels = NULL,
  compare_gradient = TRUE,
  min_gradient = 1e-05
)

Arguments

surface_a, surface_b: One-layer continuous head rasters.
direction: Signed-difference order.
align: Alignment action; mismatch errors by default.
template: Explicit target for align = "template".
resampling: Continuous bilinear or explicit nearest-neighbor alignment.
contour_levels: Optional head contour levels.
compare_gradient: Compare modeled gradient magnitude and direction.
min_gradient: Threshold below which direction is undefined.

Value

A potentiomap_surface_comparison with difference/support/gradient rasters, contour displacement, summaries, and an alignment manifest.

Examples

a <- terra::rast(nrows = 3, ncols = 3, xmin = 0, xmax = 3, ymin = 0, ymax = 3,
                 crs = "EPSG:26920", vals = 1:9)
cmp <- ps_compare_surfaces(a, a + 1)
cmp$summary
#>   direction common_cells only_a_cells only_b_cells common_area only_a_area
#> 1 b_minus_a            9            0            0           9           0
#>   only_b_area mean_difference mean_absolute_difference rmse minimum_difference
#> 1           0               1                        1    1                  1
#>   maximum_difference
#> 1                  1
# A modeled difference is not a storage or water-budget estimate.