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Plot sampled cross-sections

Source: R/transects.R
plot_cross_sections.Rd

Plots raster values against transect distance.

Usage

plot_cross_sections(
  samples,
  value_col = NULL,
  group_col = "transect_id",
  color_col = NULL,
  show_legend = TRUE,
  points = FALSE,
  mean_profile = FALSE,
  mean_profile_na_rm = TRUE,
  normalize_distance = FALSE,
  profile_direction = c("top_to_bottom", "bottom_to_top", "as_sampled", "max_to_min",
    "min_to_max", "high_to_low", "low_to_high"),
  positive_depth = NULL,
  depth_increases_down = TRUE,
  title = NULL,
  subtitle = NULL,
  caption = NULL
)

Arguments

samples

Output from sample_transects().

value_col

Optional value column.

group_col

Grouping column for transect lines.

color_col

Optional column used to color profiles. Defaults to group_col.

show_legend

Logical. Show the line-color legend.

points

Logical. Draw sample points over profile lines.

mean_profile

Logical. Overlay an interpolated mean profile across transects.

mean_profile_na_rm

Logical. Remove missing interpolated profile values when averaging the mean profile. The default, TRUE, lets the mean profile use the full available distance range rather than stopping where the shortest transect ends. Set to FALSE to require every profile to contribute at each distance.

normalize_distance

Logical. Plot distance as 0-1 normalized position along each transect.

profile_direction

Direction used to orient distance before plotting. "top_to_bottom" (the default) orients bathymetric or elevation profiles from the shallow or top endpoint toward the deeper or bottom endpoint. With negative-elevation bathymetry this means higher numeric values to lower numeric values. With positive-depth bathymetry, set positive_depth = TRUE so the profile runs from lower depth values to higher depth values. "bottom_to_top" reverses that convention. "max_to_min" and "min_to_max" provide explicit numeric endpoint controls for metrics, and "as_sampled" preserves the sampled line order. Legacy values "high_to_low" and "low_to_high" are accepted as aliases for "top_to_bottom" and "bottom_to_top".

positive_depth

Logical depth convention for value_col. This affects top-to-bottom profile orientation for depth-like variables and y-axis display for positive-depth values.

depth_increases_down

Logical. If TRUE, positive-depth profiles are plotted with a reversed y-axis so larger depths appear lower in the panel.

title, subtitle, caption

Plot text.

Value

A ggplot object.

See also

sample_transects(), plot_depth_profile()

Examples

if (requireNamespace("ggplot2", quietly = TRUE)) {
  bathy <- read_bathy(blueterra_example("bathy"))
  zones <- terra::vect(blueterra_example("zones"))
  transects <- make_transects(zones[1, ], spacing = 100, bathy = bathy)
  samples <- sample_transects(transects, bathy, n = 5)
  plot_cross_sections(samples)
}