netplot

An alternative graph visualization tool that emphasizes aesthetics, providing default parameters that deliver out-of-the-box lovely visualizations.

Some features:

1. Auto-scaling of vertices using sizes relative to the plotting device.
2. Embedded edge color mixer.
3. True curved edges drawing.
4. User-defined edge curvature.
5. Nicer vertex frame color.
6. Better use of space-filling the plotting device.

The package uses the grid plotting system (just like ggplot2).

Installation

You can install the released version of netplot from CRAN with:

install.packages("netplot")

And the development version from GitHub with:

# install.packages("devtools")
devtools::install_github("USCCANA/netplot")

Example

This is a basic example which shows you how to solve a common problem:

library(igraph)
#> 
#> Attaching package: 'igraph'
#> The following objects are masked from 'package:stats':
#> 
#>     decompose, spectrum
#> The following object is masked from 'package:base':
#> 
#>     union
library(netplot)
#> Loading required package: grid
#> 
#> Attaching package: 'netplot'
#> The following object is masked from 'package:igraph':
#> 
#>     ego
set.seed(1)
data("UKfaculty", package = "igraphdata")
l <- layout_with_fr(UKfaculty)
#> This graph was created by an old(er) igraph version.
#>   Call upgrade_graph() on it to use with the current igraph version
#>   For now we convert it on the fly...

plot(UKfaculty, layout = l) # ala igraph

V(UKfaculty)$ss <- runif(vcount(UKfaculty))
nplot(UKfaculty, layout = l) # ala netplot

sna::gplot(intergraph::asNetwork(UKfaculty), coord=l)

UKfaculty

# Random names
set.seed(1)
nam <- sample(babynames::babynames$name, vcount(UKfaculty))

ans <- nplot(
  UKfaculty,
  layout                = l,
  vertex.color          = ~ Group,
  vertex.label          = nam,
  vertex.size.range     = c(.01, .04, 4),
  vertex.label.col      =  "black",
  vertex.label.fontface = "bold",
  bg.col                = "transparent",
  vertex.label.show     = .5,
  vertex.label.range    = c(10, 25),
  edge.width.range      = c(1, 4, 5)
  )


# Plot it!
ans

Starting version 0.2-0, we can use gradients!

ans |>
  set_vertex_gpar(
    element = "core",
    fill = lapply(get_vertex_gpar(ans, "frame", "col")$col, \(i) {
      radialGradient(c("white", i), cx1=.8, cy1=.8, r1=0)
      }))

USairports

# Loading the data
data(USairports, package="igraphdata")

# Generating a layout naively
layout   <- V(USairports)$Position
#> This graph was created by an old(er) igraph version.
#>   Call upgrade_graph() on it to use with the current igraph version
#>   For now we convert it on the fly...
layout   <- do.call(rbind, lapply(layout, function(x) strsplit(x, " ")[[1]]))
layout[] <- stringr::str_remove(layout, "^[a-zA-Z]+")
layout   <- matrix(as.numeric(layout[]), ncol=2)

# Some missingness
layout[which(!complete.cases(layout)), ] <- apply(layout, 2, mean, na.rm=TRUE)

# Have to rotate it (it doesn't matter the origin)
layout <- netplot:::rotate(layout, c(0,0), pi/2)

# Simplifying the network
net <- simplify(USairports, edge.attr.comb = list(
  weight = "sum",
  name   = "concat",
  Passengers = "sum",
  "ignore"
))

# Pretty graph
nplot(
  net,
  layout            = layout,
  edge.width        = ~ Passengers,
  edge.color        = 
    ~ ego(col = "white", alpha = 0) + alter(col = "yellow", alpha = .75),
  skip.vertex       = TRUE,
  skip.arrows       = TRUE,
  edge.width.range  = c(.75, 4, 4), 
  bg.col            = "black",
  edge.line.breaks  = 10
  )