Calculate a vertical hydraulic gradient

Uses absolute upper and lower observation elevations. With an upward-positive convention, the primary gradient is (lower_head - upper_head) / (upper_elevation - lower_elevation). The result indicates potential vertical direction and is not vertical groundwater flux.

Usage

ps_vertical_gradient(
  upper_head,
  lower_head,
  upper_elevation,
  lower_elevation,
  positive = c("upward", "downward"),
  tolerance = 0,
  align = c("error", "to_upper", "to_lower", "template"),
  template = NULL,
  event_metadata = NULL
)

Arguments

upper_head, lower_head

Numeric paired heads or one-layer rasters.

upper_elevation, lower_elevation

Matching absolute elevations, not unidentified depths.

positive

Sign convention.

tolerance

Nonnegative near-zero gradient tolerance.

align, template

Explicit raster alignment controls.

event_metadata

Optional list documenting compatible event, datum, units, interval and screen-midpoint assumptions.

Value

A potentiomap_vertical_gradient with component products, direction class, support, and sign convention. No flux field is returned.

Examples

vg <- ps_vertical_gradient(10, 12, 100, 90)
vg$gradient
#> [1] 0.2
# The positive gradient indicates upward driving potential, not flux.