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Scatterplot with optional horizontal threshold lines

Source: R/scatterplot.R
scatterplot.Rd

This function creates a scatterplot from a data frame, optionally coloring points by a grouping column and adding horizontal threshold lines. Supports both static ggplot2 plots and interactive plotly plots with a linear/log toggle.

Usage

scatterplot(
  data,
  x = c("station_name", "sample_date"),
  parameter = NULL,
  hline = NULL,
  hline_group_col = NULL,
  hline_value_col = NULL,
  hline_style = list(linetype = "dashed", size = 0.8),
  max_hlines = 5,
  interactive = TRUE,
  verbose = TRUE
)

Arguments

data

A data.frame or tibble containing at least the following columns: "station_name", "sample_date", "value", "parameter", "unit".

x

Character. The column to use for the x-axis. Either "station_name" or "sample_date".

parameter

Optional character. If provided, only data for this parameter will be plotted. If NULL, the function will plot the first parameter found in the dataset.

hline

Numeric or data.frame. Horizontal line(s) to add. If numeric, a single line is drawn at that y-value. If a data.frame, must contain hline_group_col and hline_value_col columns.

hline_group_col

Character. Column used for grouping when hline is a data.frame and/or for coloring points (optional).

hline_value_col

Character. Column in hline used for the y-values of horizontal lines.

hline_style

List. Appearance settings for horizontal lines. Should contain linetype and size.

max_hlines

Integer. Maximum number of horizontal line groups to display per parameter when hline is a data.frame.

interactive

Logical. If TRUE, returns an interactive plotly plot; if FALSE, returns a static ggplot2 plot.

verbose

Logical. If TRUE, messages will be displayed during execution. Defaults to TRUE.

Value

A ggplot object (if interactive = FALSE) or a plotly object (if interactive = TRUE).

Details

  • If hline is numeric, a single horizontal line is drawn across the plot.

  • If hline is a data.frame, only the first max_hlines groups (sorted alphabetically) are displayed.

  • Points can be colored by hline_group_col if provided.

  • Interactive plots include buttons to switch between linear and log y-axis scales.

See also

load_shark4r_stats for loading threshold or summary statistics that can be used to define horizontal lines in the plot.

Examples

if (FALSE) { # \dontrun{
scatterplot(
  data = my_data,
  x = "station_name",
  parameter = "Chlorophyll-a",
  hline = c(10, 20)
)

scatterplot(
  data = my_data,
  x = "sample_date",
  parameter = "Bacterial abundance",
  hline = thresholds_df,
  hline_group_col = "location_sea_basin",
  hline_value_col = "P99"
)
} # }