plot_alluvial: Plot Alluvial Diagram

In cograph: Analysis and Visualization of Complex Networks

Plot Alluvial Diagram

Description

Creates an alluvial (Sankey) diagram showing aggregated flows between states. This is an alias for plot_transitions() with aggregated flows (default).

Usage

plot_alluvial(
  x,
  from_title = "From",
  to_title = "To",
  title = NULL,
  from_colors = NULL,
  to_colors = NULL,
  flow_fill = "#888888",
  flow_alpha = 0.4,
  flow_color_by = NULL,
  flow_border = NA,
  flow_border_width = 0.5,
  node_width = 0.08,
  node_border = NA,
  node_spacing = 0.02,
  label_size = 3.5,
  label_position = c("beside", "inside", "above", "below", "outside"),
  label_halo = TRUE,
  label_color = "black",
  label_fontface = "plain",
  label_nudge = 0.02,
  title_size = 5,
  title_color = "black",
  title_fontface = "bold",
  curve_strength = 0.6,
  show_values = FALSE,
  value_position = c("center", "origin", "destination", "outside_origin",
    "outside_destination"),
  value_size = 3,
  value_color = "black",
  value_halo = NULL,
  value_fontface = "bold",
  value_nudge = 0.03,
  value_min = 0,
  show_totals = FALSE,
  total_size = 4,
  total_color = "white",
  total_fontface = "bold",
  conserve_flow = TRUE,
  min_flow = 0,
  threshold = 0,
  value_digits = 2,
  column_gap = 1
)

Arguments

x	Input data in one of several formats: A transition matrix (rows = from, cols = to, values = counts) Two vectors: pass before as x and after as second argument (contingency table computed automatically, like chi-square) A 2-column data frame (raw observations; table computed automatically) A data frame with columns: from, to, count A list of matrices for multi-step transitions
from_title	Title for the left column. Default "From". For multi-step, use a vector of titles (e.g., c("T1", "T2", "T3", "T4")).
to_title	Title for the right column. Default "To". Ignored for multi-step.
title	Optional plot title. Applied via ggplot2::labs(title = title).
from_colors	Colors for left-side nodes. Default uses palette.
to_colors	Colors for right-side nodes. Default uses palette.
flow_fill	Fill color for flows. Default "#888888" (grey). Ignored if flow_color_by is set.
flow_alpha	Alpha transparency for flows. Default 0.4.
flow_color_by	Color flows by "source", "destination", or NULL (use flow_fill). Default NULL.
flow_border	Border color for flows. Default NA (no border).
flow_border_width	Line width for flow borders. Default 0.5.
node_width	Width of node rectangles (0-1 scale). Default 0.08.
node_border	Border color for nodes. Default NA (no border).
node_spacing	Vertical spacing between nodes (0-1 scale). Default 0.02.
label_size	Size of node labels. Default 3.5.
label_position	Position of node labels: "beside" (default), "inside", "above", "below", "outside". Applied to first and last columns. See mid_label_position for middle columns.
label_halo	Logical: add white halo around labels for readability? Default TRUE.
label_color	Color of state name labels. Default "black".
label_fontface	Font face of state name labels ("plain", "bold", "italic", "bold.italic"). Default "plain".
label_nudge	Distance between node edge and label (in plot units). Default 0.02. Increase for more spacing.
title_size	Size of column titles. Default 5.
title_color	Color of column title text. Default "black".
title_fontface	Font face of column titles. Default "bold".
curve_strength	Controls bezier curve shape (0-1). Default 0.6.
show_values	Logical: show transition counts on flows? Default FALSE.
value_position	Position of flow values: "center", "origin", "destination", "outside_origin", "outside_destination". Default "center".
value_size	Size of value labels on flows. Default 3.
value_color	Color of value labels. Default "black".
value_halo	Logical: add halo around flow value labels? Default NULL (inherits from label_halo).
value_fontface	Font face of flow value labels. Default "bold".
value_nudge	Distance of value labels from node edge when using "origin" or "destination" positions. Default 0.03.
value_min	Minimum count to show a flow value label. Default 0 (show all). Use to hide small flows (e.g., value_min = 100).
show_totals	Logical: show total counts on nodes? Default FALSE.
total_size	Size of total labels. Default 4.
total_color	Color of total labels. Default "white".
total_fontface	Font face of total labels. Default "bold".
conserve_flow	Logical: should left and right totals match? Default TRUE. When FALSE, each side scales independently (allows for "lost" or "gained" items).
min_flow	Minimum flow value to display. Default 0 (show all).
threshold	Minimum edge weight to display. Flows below this value are removed. Combined with min_flow: effective minimum is max(threshold, min_flow). Default 0.
value_digits	Number of decimal places for flow value labels and node totals. Default 2.
column_gap	Horizontal spread of columns (0-1). Default 1 uses full width. Use smaller values (e.g., 0.6) to bring columns closer together.

Value

A ggplot2 object.

See Also

plot_transitions, plot_trajectories

Examples

## Not run: 
# From a transition matrix
mat <- matrix(c(50, 10, 5, 15, 40, 10), 2, 3)
rownames(mat) <- c("A", "B")
colnames(mat) <- c("X", "Y", "Z")
plot_alluvial(mat)

## End(Not run)

cograph documentation built on April 1, 2026, 1:07 a.m.