prep_flowmap: prep_flowmap

In flowmapper: Draw Flows (Migration, Goods, Money, Information) on 'ggplot2' Plots

prep_flowmap

Description

prep_flowmap

Usage

prep_flowmap(
  flowdat = NULL,
  od = NULL,
  nodes = NULL,
  k_nodes = NULL,
  node_buffer_factor = 1.2,
  node_radius_factor = 1,
  edge_offset_factor = 1,
  node_fill_factor = NULL,
  edge_width_factor = 1.2,
  arrow_point_angle = 45
)

Arguments

flowdat	Input dataframe. See details below.
od	As an alternative to flowdat, dataframe with the origin-destination pairs and the flow between them. Must contain the columns o, d, value. nodes must be provided as well. See details below.
nodes	As an alternative to flowdat, a dataframe with the nodes of the network. Must contain the columns name, x, y. See details below.
k_nodes	Number of clusters to group nodes into. If defined, nodes will be clustered hierarchically based on spatial proximity. By default, no clustering will be applied.
node_buffer_factor	Controls the distance between the nodes and the edges ( in multiple of the nodes' radii).
node_radius_factor	Controls the size of the nodes.
edge_offset_factor	Controls the distance between the parallel arrows.
node_fill_factor	Controls the downscaling of the fill of the nodes ( as to not outshine the edges ).
edge_width_factor	Controls the width of the edges.
arrow_point_angle	Controls the pointiness of the edges.

Value

A list with two dataframes: edges and nodes. The edges dataframe contains the coordinates of the edges, and the nodes dataframe contains the coordinates of the nodes. Additional list elements contain the maximum and minimum width of the arrows.

Examples

testdata <-
data.frame(
 id_a = c("X1","X2","X3","X3","X1"),
 id_b = c("X8","X7","X1","X8","X7"),
 xa = c(2,14,10,10,2),
 ya = c(6,10,9,9,6),
 xb = c(10,4,2,10,4),
 yb = c(4,10,6,4,10),
 flow_ab = c(2,1,1,1,1),
 flow_ba = c(5,1,1,1,2))
flowmapper:::prep_flowmap(testdata)

flowmapper documentation built on June 11, 2025, 5:08 p.m.