Trade-off surface: catchment area vs reservoir capacity

Draws the performance surface produced by rh_grid() as a heatmap with iso-performance contours. With area on the x-axis and capacity on the y-axis (the defaults), it shows whether enlarging the roof or the tank moves the system across a target guarantee level faster. The demand (and any other parameter) is whatever was fixed in the base of rh_grid().

Usage

rh_plot_tradeoff(grid, metric = NULL, contours = TRUE, breaks = NULL)

Arguments

grid

A data frame from rh_grid().

metric

Which metric column to display; defaults to the first metric in grid. Typically "attendance_pct" (volumetric) or "reliability_pct" (time-based).

contours

Logical; overlay iso-performance contour lines. Default TRUE.

breaks

Numeric contour levels (e.g. c(80, 90, 95, 100) for a percentage metric). Default NULL (automatic).

Value

A ggplot2 object.

Examples

g <- rh_grid(precip_pi$value,
             base = list(demand = 6.6, runoff = 0.85, efficiency = 1),
             x = "area", x_values = seq(500, 6000, length.out = 12),
             y = "capacity", y_values = seq(100, 1200, length.out = 12),
             metrics = "attendance_pct",
             dates = precip_pi$date, climatology = TRUE)
if (requireNamespace("ggplot2", quietly = TRUE)) {
  rh_plot_tradeoff(g, breaks = c(50, 70, 90, 100))
}