vizNetConnectogram: vizNetConnectogram

In FCtools: Functional Connectivity Tools

vizNetConnectogram

Description

Generate a Network Connectogram from a Vector of FC network or edge data

Usage

vizNetConnectogram(
  FC_dat,
  show.sig = TRUE,
  title = NULL,
  title.size = 10,
  hot = "#F8766D",
  cold = "#00BFC4",
  node.text.size = 2,
  node.size = 2,
  node.color = "black",
  edge.thickness = 1.5,
  sig.color = "darkgrey",
  legend = TRUE,
  legend.title = "Standardized Coefficient",
  legend.title.size = 6,
  legend.text.size = 5,
  expand = 1.1,
  limits,
  filename,
  width = 1000,
  height = 700
)

Arguments

FC_dat	a matrix of edge values with 4005, 7021, 23871 or 30135 columns
show.sig	Logical. If TRUE, significant edges will be outlined with sig.color. Default is FALSE.
title	Character string for the plot title. Default is NULL (no title).
title.size	Numeric. Font size of the plot title. Default is 10.
hot	Character. Color used for positive edges and node highlights. Default is "#F8766D" (red).
cold	Character. Color used for negative edges and node highlights. Default is "#00BFC4" (teal).
node.text.size	Numeric. Size of the node label text. Default is 2.
node.size	Numeric. Size of the node points. Default is 2.
node.color	Character. Fill color of the node points. Default is "black".
edge.thickness	Numeric. Width of the edges (and node border stroke). Default is 2.
sig.color	Character. Color for the significant edges. Default is "darkgrey"
legend	Logical. If TRUE, a continuous color bar legend is added to the plot. Default is TRUE.
legend.title	Character string for the legend title. Default is "Standardized Coefficient".
legend.title.size	Numeric. Font size of the legend title. Default is 8.
legend.text.size	Numeric. Font size of the legend tick labels. Default is 5.
expand	Numeric. Multiplicative expansion factor applied to the x and y axis limits to prevent node labels from being clipped. Default is 1.1.
limits	Numeric vector of length 2. Color scale limits for the edge alpha and node alpha mappings. If not supplied, limits are set automatically to c(0, max(abs(weight))) inside the function.
filename	Character. Path/filename for the output PNG. If the argument is omitted entirely, no file is written.
width	Integer. Width of the saved PNG in pixels. Default is 1000.
height	Integer. Height of the saved PNG in pixels. Default is 1000.

Details

Creates a circular network connectogram (chord diagram) from a data frame of connectivity results, visualizing edge weights and their signs using color and transparency. Node self-connections (diagonal elements) are highlighted on the node border. Optionally saves the plot to a PNG file.

Row names of results must follow the pattern "nodeA to nodeB". Self-connections (from == to) are extracted to colour and shade node borders: if all diagonal values are > 1 the border is drawn in hot; if all are < 1 it is drawn in cold. The diagonal entries are removed before the igraph graph object is constructed.

Edge colour encodes sign (hot = positive, cold = negative) and edge transparency encodes absolute magnitude.

The function relies on igraph, ggraph, and ggplot2.

Value

A ggraph/ggplot2 plot object (invisibly returned via print and return). As a side effect the plot is printed to the active graphics device, and — if filename is provided — written to a 300 dpi PNG file.

Examples

demomat=get('demomat')
vizNetConnectogram(colMeans(demomat))

FCtools documentation built on Sept. 15, 2026, 5:09 p.m.