Package 'netplot'

Title: Beautiful Graph Drawing
Description: A graph visualization engine that emphasizes on aesthetics at the same time providing default parameters that yield out-of-the-box-nice visualizations. The package is built on top of 'The Grid Graphics Package' and seamlessly work with 'igraph' and 'network' objects.
Authors: George Vega Yon [aut, cre] , Porter Bischoff [aut]
Maintainer: George Vega Yon <[email protected]>
License: MIT + file LICENSE
Version: 0.3-0
Built: 2024-11-15 16:35:12 UTC
Source: https://github.com/usccana/netplot

Help Index

Function to create a color key

Description

Function to create a color key

Usage

colorkey(
  x0,
  y0,
  x1,
  y1,
  cols = c("white", "steelblue"),
  tick.range = c(0, 1),
  tick.marks = seq(tick.range[1], tick.range[2], length.out = 5L),
  label.from = NULL,
  label.to = NULL,
  nlevels = 100,
  main = NULL,
  relative = TRUE,
  tick.args = list(),
  label.args = list(),
  main.args = list()
)

Arguments

x0, x1, y0, y1

Numeric scalars. Coordinates of the lower left and upper right points where the color key will be drawn as proportion of the plotting region.
cols

Character scalar. Colors specifications to create the color palette.
tick.range, tick.marks

Numeric vectors specifying the range and the tickmarks respectively.
label.from, label.to

Character scalar. Labels of the lower and upper values of the color key.
nlevels

Integer scalar. Number of levels to extrapolate.
main

Character scalar. Title of the colorkey.
relative

Logical scalar. When TRUE the color key is drawn relative to the plotting region area taking ⁠x0, x1, y0, y1⁠ as relative location.
tick.args, label.args, main.args

Lists of arguments passed to graphics::text for drawing ticks, labels and main respectively.

Value

NULL.

Examples

set.seed(22231)

# A random figure
dat <- matrix(runif(100*3), ncol = 3)
col <- colorRamp2(c("blue", "white", "red"))

plot(
  dat[,1], dat[,2],
  col = rgb(col(dat[,3]), maxColorValue=255),
  cex=2, pch=20
  )

# Pretty color key
colorkey(
  x0 = .60, y0 = .80,
  x1 = .95, y1 = .95,
  cols = c("blue", "white", "red"),
  main = "Some color scale"
)

A faster implementation of grDevices::colorRamp for linear interpolation.

Description

A faster implementation of grDevices::colorRamp for linear interpolation.

Usage

colorRamp2(x, alpha = TRUE, thresholds = NULL)

Arguments

x

A vector of colors.
alpha

Logical scalar. When TRUE This implementation of colorRamp can be 2 or more times faster than the grDevices version. It is intended for consecutive calls (i.e. in a loop) to improve performance. It is equivalent to the linear interpolation of the function colorRamp.
thresholds

A numeric vector of length length(x). Optional threshold levels so that the mixing can be different that even.

Value

A function as in grDevices::colorRamp.

Examples

# Creating a function for 2 colors
myf <- colorRamp2(c("black", "steelblue"))
f   <- colorRamp(c("black", "steelblue"))

plot.new()
plot.window(xlim = c(0,2), ylim = c(1, 11))

# These should be the same colors
rect(
  xleft   = 0,
  xright  = 1,
  ybottom = 1:10,
  ytop    = 2:11,
  col = rgb(myf((1:10)/10), maxColorValue = 255)
  )
rect(
  xleft   = 1,
  xright  = 2,
  ybottom = 1:10,
  ytop    = 2:11,
  col = rgb(f((1:10)/10), maxColorValue = 255)
)

# Another example setting different thresholds
myf  <- colorRamp2(c("black", "steelblue"))
myf2 <- colorRamp2(c("black", "steelblue"), thresholds=c(0, .7))

plot.new()
plot.window(xlim = c(0,2), ylim = c(1, 11))

# These should be the same colors
rect(
  xleft   = 0,
  xright  = 1,
  ybottom = 1:10,
  ytop    = 2:11,
  col = rgb(myf((1:10)/10), maxColorValue = 255)
  )
rect(
  xleft   = 1,
  xright  = 2,
  ybottom = 1:10,
  ytop    = 2:11,
  col = rgb(myf2((1:10)/10), maxColorValue = 255)
)

Find a vertex in the current plot

Description

This function is a wrapper of grid::grid.locator(), and provides a way to find the coordinates of a vertex in the current plot. It is useful to identify the vertex that is being clicked in a plot.

Usage

locate_vertex(x = NULL)

Arguments

x

An object of class netplot

Details

This function only works in interactive mode. Once it is called, the user can click on a vertex in the plot. The function will return the name of the vertex, the x and y coordinates and the viewport where it is located. If x is not specified, the last plotted netplot object will be used.

Value

A list with the name of the vertex, the x and y coordinates and the viewport where it is located.

Examples

library(igraph)
library(netplot)
set.seed(1)
x <- sample_smallworld(1, 200, 5, 0.03)

# Plotting
nplot(x)

# Clicking (only works in interactive mode)
if (interactive()) {
 res <- locate_vertex()
 print(res)
}

Create a vector of colors for vertices and edges

Description

Using vertex/edge attributes, these functions return vectors of colors that can be used either during the creation of the nplot object, or afterwards when changing gpar (graphical parameter) values with set_gpar.

Usage

make_colors(dat, categorical = FALSE, color_map = grDevices::hcl.colors)

make_edges_colors(x, eattr, ...)

make_vertex_colors(x, vattr, ...)

Arguments

dat

A vector of data to generate the color from.
categorical

Logical. When TRUE sets the colors as categories.
color_map

A function to generate a palette.
x

A graph of class network or igraph.
...

Further arguments passed to make_colors.
vattr, eattr

Character. Names of either vertex or edge variables to be used for generating the colors.

Details

If no attribute is provided, then by defaul the colors are set according to indegree.

x can be either a graph of class igraph or network.

Value

A vector of colors with the attribute color_map. The color map used to generate the colors.

Examples

data(UKfaculty, package="igraphdata")
col <- make_vertex_colors(UKfaculty, "Group")

if (require(magrittr)) {

  nplot(UKfaculty) %>%
    set_vertex_gpar("core", fill = col, col=col) %>%
    set_vertex_gpar("frame", fill = col, col=col, alpha=.7) %>%
    set_edge_gpar(col="gray50", fill="gray50", alpha=.5)
}

Formulas in netplot

Description

Edge colors in both nplot() and set_edge_gpar() can be specified using a formula based on ego() and alter() (source and target). This way the user can set various types of combination varying the mixing of the colors, the alpha levels, and the actual mixing colors to create edge colors.

Usage

color_formula(x, col, alpha, env, type, mix = 1, postfix = NULL)

ego(...)

alter(...)

Arguments

x

An object of class netplot.
col

Any valid color. Can be a single color or a vector.
alpha

Number. Alpha levels
env, type, postfix

For internal use only.
mix

Number. For mixing colors between ego and alter
...

Passed to color_formula.

Value

Nothing. These functions are called internally when using formulas. color_formula modifies the environment env.

Examples

if (require(gridExtra) & require(magrittr)) {
  library(igraph)
  net <- make_ring(4)

  set.seed(1)
  np <- nplot(net, vertex.color = grDevices::hcl.colors(4), vertex.size.range=c(.1, .1))
  np %<>% set_edge_gpar(lwd = 4)

  grid.arrange(
    np,
    np %>% set_edge_gpar(col =~ego + alter),
    np %>% set_edge_gpar(col =~ego(alpha=0) + alter),
    np %>% set_edge_gpar(col =~ego + alter(alpha=0)),
    np %>% set_edge_gpar(col =~ego(mix=0) + alter(mix=1)),
    np %>% set_edge_gpar(col =~ego(mix=1) + alter(mix=0))
  )
}

Plot a network

Description

This is a description.

Usage

nplot(
  x,
  layout,
  vertex.size = 1,
  bg.col = "transparent",
  vertex.nsides = 10,
  vertex.color = grDevices::hcl.colors(1),
  vertex.size.range = c(0.01, 0.03, 4),
  vertex.frame.color = NULL,
  vertex.rot = 0,
  vertex.frame.prop = 0.2,
  vertex.label = NULL,
  vertex.label.fontsize = NULL,
  vertex.label.color = adjustcolor("black", alpha.f = 0.8),
  vertex.label.fontfamily = "sans",
  vertex.label.fontface = "plain",
  vertex.label.show = 0.3,
  vertex.label.range = c(5, 15),
  edge.width = 1,
  edge.width.range = c(1, 2),
  edge.arrow.size = NULL,
  edge.color = ~ego(alpha = 0.1, col = "gray") + alter,
  edge.curvature = pi/3,
  edge.line.lty = "solid",
  edge.line.breaks = 5,
  sample.edges = 1,
  skip.vertex = FALSE,
  skip.edges = FALSE,
  skip.arrows = skip.edges,
  add = FALSE,
  zero.margins = TRUE,
  edgelist
)

## S3 method for class 'igraph'
nplot(
  x,
  layout = igraph::layout_nicely(x),
  vertex.size = igraph::degree(x, mode = "in"),
  bg.col = "transparent",
  vertex.nsides = 10,
  vertex.color = grDevices::hcl.colors(1),
  vertex.size.range = c(0.01, 0.03, 4),
  vertex.frame.color = NULL,
  vertex.rot = 0,
  vertex.frame.prop = 0.2,
  vertex.label = igraph::vertex_attr(x, "name"),
  vertex.label.fontsize = NULL,
  vertex.label.color = adjustcolor("black", alpha.f = 0.8),
  vertex.label.fontfamily = "sans",
  vertex.label.fontface = "plain",
  vertex.label.show = 0.3,
  vertex.label.range = c(5, 15),
  edge.width = igraph::edge_attr(x, "weight"),
  edge.width.range = c(1, 2),
  edge.arrow.size = NULL,
  edge.color = ~ego(alpha = 0.1, col = "gray") + alter,
  edge.curvature = pi/3,
  edge.line.lty = "solid",
  edge.line.breaks = 5,
  sample.edges = 1,
  skip.vertex = FALSE,
  skip.edges = FALSE,
  skip.arrows = !igraph::is_directed(x),
  add = FALSE,
  zero.margins = TRUE,
  edgelist
)

## S3 method for class 'network'
nplot(
  x,
  layout = sna::gplot.layout.kamadakawai(x, NULL),
  vertex.size = sna::degree(x, cmode = "indegree"),
  bg.col = "transparent",
  vertex.nsides = 10,
  vertex.color = grDevices::hcl.colors(1),
  vertex.size.range = c(0.01, 0.03, 4),
  vertex.frame.color = NULL,
  vertex.rot = 0,
  vertex.frame.prop = 0.2,
  vertex.label = network::get.vertex.attribute(x, "vertex.names"),
  vertex.label.fontsize = NULL,
  vertex.label.color = adjustcolor("black", alpha.f = 0.8),
  vertex.label.fontfamily = "sans",
  vertex.label.fontface = "plain",
  vertex.label.show = 0.3,
  vertex.label.range = c(5, 15),
  edge.width = 1,
  edge.width.range = c(1, 2),
  edge.arrow.size = NULL,
  edge.color = ~ego(alpha = 0.1, col = "gray") + alter,
  edge.curvature = pi/3,
  edge.line.lty = "solid",
  edge.line.breaks = 5,
  sample.edges = 1,
  skip.vertex = FALSE,
  skip.edges = FALSE,
  skip.arrows = !network::is.directed(x),
  add = FALSE,
  zero.margins = TRUE,
  edgelist
)

## S3 method for class 'matrix'
nplot(
  x,
  layout,
  vertex.size = 1,
  bg.col = "transparent",
  vertex.nsides = 10,
  vertex.color = grDevices::hcl.colors(1),
  vertex.size.range = c(0.01, 0.03, 4),
  vertex.frame.color = NULL,
  vertex.rot = 0,
  vertex.frame.prop = 0.2,
  vertex.label = NULL,
  vertex.label.fontsize = NULL,
  vertex.label.color = adjustcolor("black", alpha.f = 0.8),
  vertex.label.fontfamily = "sans",
  vertex.label.fontface = "plain",
  vertex.label.show = 0.3,
  vertex.label.range = c(5, 15),
  edge.width = 1,
  edge.width.range = c(1, 2),
  edge.arrow.size = NULL,
  edge.color = ~ego(alpha = 0.1, col = "gray") + alter,
  edge.curvature = pi/3,
  edge.line.lty = "solid",
  edge.line.breaks = 5,
  sample.edges = 1,
  skip.vertex = FALSE,
  skip.edges = FALSE,
  skip.arrows = skip.edges,
  add = FALSE,
  zero.margins = TRUE,
  edgelist
)

## Default S3 method:
nplot(
  x,
  layout,
  vertex.size = 1,
  bg.col = "transparent",
  vertex.nsides = 10,
  vertex.color = grDevices::hcl.colors(1),
  vertex.size.range = c(0.01, 0.03, 4),
  vertex.frame.color = NULL,
  vertex.rot = 0,
  vertex.frame.prop = 0.2,
  vertex.label = NULL,
  vertex.label.fontsize = NULL,
  vertex.label.color = adjustcolor("black", alpha.f = 0.8),
  vertex.label.fontfamily = "sans",
  vertex.label.fontface = "plain",
  vertex.label.show = 0.3,
  vertex.label.range = c(5, 15),
  edge.width = 1,
  edge.width.range = c(1, 2),
  edge.arrow.size = NULL,
  edge.color = ~ego(alpha = 0.1, col = "gray") + alter,
  edge.curvature = pi/3,
  edge.line.lty = "solid",
  edge.line.breaks = 5,
  sample.edges = 1,
  skip.vertex = FALSE,
  skip.edges = FALSE,
  skip.arrows = skip.edges,
  add = FALSE,
  zero.margins = TRUE,
  ...,
  edgelist
)

## S3 method for class 'netplot'
print(x, y = NULL, newpage = TRUE, legend = TRUE, ...)

Arguments

x

A graph. It supports networks stored as igraph, network, and matrices objects (see details).
layout

Numeric two-column matrix with the graph layout in x/y positions of the vertices.
vertex.size

Numeric vector of length vcount(x). Absolute size of the vertex from 0 to 1.
bg.col

Color of the background.
vertex.nsides

Numeric vector of length vcount(x). Number of sizes of the vertex. E.g. three is a triangle, and 100 approximates a circle.
vertex.color

Vector of length vcount(x). Vertex HEX or built in colors.
vertex.size.range

Numeric vector of length 3. Relative size for the minimum and maximum of the plot, and curvature of the scale. The third number is used as size^rel[3].
vertex.frame.color

Vector of length vcount(x). Border of vertex in HEX or built in colors.
vertex.rot

Vector of length vcount(x) in Radians. Passed to npolygon, elevation degree from which the polygon is drawn.
vertex.frame.prop

Vector of length vcount(x). What proportion of the vertex does the frame occupy (values between 0 and 1).
vertex.label

Character vector of length vcount(x). Labels.
vertex.label.fontsize

Numeric vector.
vertex.label.color

Vector of colors of length vcount(x).
vertex.label.fontfamily

Character vector of length vcount(x).
vertex.label.fontface

See grid::gpar
vertex.label.show

Numeric scalar. Proportion of labels to show as the top ranking according to vertex.size.
vertex.label.range

Numeric vector of size 2 or 3. Relative scale of vertex.label.fontsize in points (see grid::gpar).
edge.width

Vector of length ecount(x) from 0 to 1. All edges will be the same size.
edge.width.range

Vector of length ecount(x) from 0 to 1. Adjusting width according to weight.
edge.arrow.size

Vector of length ecount(x) from 0 to 1.
edge.color

A vector of length ecount(x). In HEX or built in colors. Can be NULL in which case the color is picked as a mixture between ego and alters' vertex.color values.
edge.curvature

Numeric vector of length ecount(x). Curvature of edges in terms of radians.
edge.line.lty

Vector of length ecount(x). Line types in R (e.g.- 1 = Solid, 2 = Dashed, etc).
edge.line.breaks

Vector of length ecount(x). Number of vertices to draw (approximate) the arc (edge).
sample.edges

Numeric scalar between 0 and 1. Proportion of edges to sample.
skip.vertex, skip.edges, skip.arrows

Logical scalar. When TRUE the object is not plotted.
add

Logical scalar.
zero.margins

Logical scalar.
edgelist

An edgelist.
y, ...

Ignored
newpage

Logical scalar. When TRUE calls grid::grid.newpage.
legend

Logical scalar. When TRUE it adds a legend.

Details

When x is of class matrix, it will be passed to igraph::graph_from_adjacency_matrix().

In the case of edge.color, the user can specify colors using netplot-formulae.

Value

An object of class c("netplot", "gTree", "grob", "gDesc"). The object has an additional set of attributes:

  • ⁠.xlim, .ylim⁠ vector of size two with the x-asis/y-axis limits.

  • .layout A numeric matrix of size vcount(x) * 2 with the vertices positions

  • .edgelist A numeric matrix, The edgelist.

In the case of nplot.default, an object of class netplot and grob (see grid::grob) with the following slots:

  • children The main grob of the object.

  • name Character scalar. The name of the plot

  • .xlim and .ylim Two vectors indicating the limits of the plot

  • .layout A two-column matrix with the location of the vertices.

  • .edgelist A two-column matrix, an edgelist.

  • .N Integer. The number of vertices.

  • .M Integer. The number of edges.

The children grob contains the following two objects:

  • background a grob rectangule.

  • graph a gTree that contains each vertex and each edge of the figure.

See Also

nplot_base

Examples

library(igraph)
library(netplot)
set.seed(1)
x <- sample_smallworld(1, 200, 5, 0.03)

plot(x) # ala igraph
nplot(x) # ala netplot

nplot using base graphics

Description

nplot using base graphics

Usage

nplot_base(
  x,
  layout = igraph::layout_nicely(x),
  vertex.size = igraph::degree(x, mode = "in"),
  bg.col = "transparent",
  vertex.nsides = 10,
  vertex.color = grDevices::hcl.colors(1),
  vertex.size.range = c(0.01, 0.03, 4),
  vertex.frame.color = grDevices::adjustcolor(vertex.color, red.f = 0.75, green.f = 0.75,
    blue.f = 0.75),
  vertex.rot = 0,
  vertex.frame.prop = 0.1,
  edge.width = NULL,
  edge.width.range = c(1, 2),
  edge.arrow.size = NULL,
  edge.color = NULL,
  edge.color.mix = 0.5,
  edge.color.alpha = c(0.1, 0.5),
  edge.curvature = pi/3,
  edge.line.lty = "solid",
  edge.line.breaks = 5,
  sample.edges = 1,
  skip.vertex = FALSE,
  skip.edges = FALSE,
  skip.arrows = skip.edges,
  add = FALSE,
  zero.margins = TRUE
)

Arguments

x

A graph. It supports networks stored as igraph, network, and matrices objects (see details).
layout

Numeric two-column matrix with the graph layout in x/y positions of the vertices.
vertex.size

Numeric vector of length vcount(x). Absolute size of the vertex from 0 to 1.
bg.col

Color of the background.
vertex.nsides

Numeric vector of length vcount(x). Number of sizes of the vertex. E.g. three is a triangle, and 100 approximates a circle.
vertex.color

Vector of length vcount(x). Vertex HEX or built in colors.
vertex.size.range

Numeric vector of length 3. Relative size for the minimum and maximum of the plot, and curvature of the scale. The third number is used as size^rel[3].
vertex.frame.color

Vector of length vcount(x). Border of vertex in HEX or built in colors.
vertex.rot

Vector of length vcount(x) in Radians. Passed to npolygon, elevation degree from which the polygon is drawn.
vertex.frame.prop

Vector of length vcount(x). What proportion of the vertex does the frame occupy (values between 0 and 1).
edge.width

Vector of length ecount(x) from 0 to 1. All edges will be the same size.
edge.width.range

Vector of length ecount(x) from 0 to 1. Adjusting width according to weight.
edge.arrow.size

Vector of length ecount(x) from 0 to 1.
edge.color

A vector of length ecount(x). In HEX or built in colors. Can be NULL in which case the color is picked as a mixture between ego and alters' vertex.color values.
edge.color.mix

Proportion of the mixing.
edge.color.alpha

Either a vector of length 1 or 2, or a matrix of size ecount(x)*2 with values in ⁠[0,1]⁠. Alpha (transparency) levels (see details)
edge.curvature

Numeric vector of length ecount(x). Curvature of edges in terms of radians.
edge.line.lty

Vector of length ecount(x). Line types in R (e.g.- 1 = Solid, 2 = Dashed, etc).
edge.line.breaks

Vector of length ecount(x). Number of vertices to draw (approximate) the arc (edge).
sample.edges

Numeric scalar between 0 and 1. Proportion of edges to sample.
skip.vertex, skip.edges, skip.arrows

Logical scalar. When TRUE the object is not plotted.
add

Logical scalar.
zero.margins

Logical scalar.

Value

nplot_base returns a list with the following components:

  • vertex.coords A list of length N where each element describes the geomtry of each vertex.

  • vertex.color A vector of colors

  • vertex.frame.coords Similar to vertex.coords, but for the frame.

  • vertex.frame.color Similar to vertex.color, but for the frame.

  • edge.color Vector of functions used to compute the edge colors.

  • edge.coords Similar to vertex.coords, the points that describe each edge.

  • edge.arrow.coords A list of matrices describing the geometry of the tip of the edges.

  • edge.width A numeric vector with edges' widths.

  • xlim, ylim Limits of the plot area.

See Also

nplot

Examples

# Same example as in nplot
library(igraph)
library(netplot)
set.seed(1)
x <- sample_smallworld(1, 200, 5, 0.03)

nplot_base(x) # ala netplot (using base)

Add legend to a netplot object

Description

Legends in grid graphics is a bit more complicated than in base graphics. The function nplot_legend is a wrapper of grid::legendGrob() that makes the process easier. Besides labels, the main visual arguments for the figure ar passed through the gp argument (see examples).

Usage

nplot_legend(
  g,
  labels,
  pch,
  gp = grid::gpar(),
  ...,
  packgrob.args = list(side = "left")
)

## S3 method for class 'netplot_legend'
print(x, y = NULL, newpage = TRUE, ...)

Arguments

g

An object of class netplot.
labels

Character vector of labels.
pch

See graphics::points().
gp

An object of class grid::gpar()
...

Further arguments passed to grid::legendGrob().
packgrob.args

List of arguments passed to grid::packGrob().
x

An object of class netplot_legend.
y

Ignored.
newpage

Logical scalar. When TRUE it calls grid::grid.newpage().

Value

A frame grob.

Examples

library(igraph)
library(netplot)
set.seed(1)
x <- sample_smallworld(1, 200, 5, 0.03)
V(x)$nsides <- sample(c(10, 4), 200, replace = TRUE)

g <- nplot(
  x,
  vertex.nsides = V(x)$nsides,
  vertex.color  = ifelse(V(x)$nsides == 4, "red", "steelblue"),
  edge.line.breaks = 5
  )

nplot_legend(
  g,
  labels = c("circle", "diamond", "edge"),
  pch    = c(21, 23, NA),
  gp     = gpar(
    fill = c("steelblue", "red", NA),
    lwd  = c(NA, NA, 1),
    col  = c(NA, NA, "purple")
    )
  )
grid.text("Legend to the left (default)", y = unit(.95, "npc"), just = "bottom")

nplot_legend(
  g,
  labels = c("circle", "diamond", "edge"),
  pch    = c(21, 23, NA),
  gp     = gpar(
    fill = c("steelblue", "red", NA),
    lwd  = c(NA, NA, 1),
    col  = c(NA, NA, "purple")
    ),
  # These two extra options set the legend to the bottom
  packgrob.args = list(side = "bottom"),
  ncol = 3
  )
grid.text("Legend bottom", y = unit(.95, "npc"), just = "bottom")

n-sided polygons Calculate the coordinates for an nsided polygon

Description

n-sided polygons Calculate the coordinates for an nsided polygon

Usage

npolygon(x = 0, y = 0, n = 6L, r = 1, d = 2 * pi/(n)/2)

Arguments

x, y

Numeric scalar. Origin of the polygon.
n

Integer scalar. Number of sides.
r

Numeric scalar. Radious of the polygon.
d

Numeric scalar. Starting degree in radians.

Value

A two column matrix with the coordinates to draw a n sided polygon.

Examples

graphics.off()
oldpar <- par(no.readonly = TRUE)

par(xpd = NA, mfrow = c(3, 3), mai = rep(0, 4))
for (n in c(2, 3, 4, 5, 6, 8, 12, 20, 50)) {

  plot.new()
  plot.window(c(-1.25,1.25), c(-1.25,1.25))

  for (i in seq(1, .0005, length.out = 200)) {
    col <- adjustcolor("tomato", alpha.f = i)
    polygon(npolygon(x=(i-1)/4, y = (i-1)/4, r = i, d = i-1, n = n),
            col = NA, border=col)
  }

  mtext(sprintf("n = %i", n), side = 1, line = -3)
}

par(oldpar)

A flexible piechart.

Description

While similar to graphics::pie(), this function is much more flexible as it allows providing different parameters for each slice of the pie. Furthermore, it allows adding the plot to the current device, making it possible to create compound piecharts.

Usage

piechart(
  x,
  labels = names(x),
  radius = 1,
  doughnut = 0,
  origin = c(0, 0),
  edges = 200,
  slice.off = 0,
  init.angle = 0,
  last.angle = 360,
  tick.len = 0.1,
  text.args = list(),
  segments.args = list(),
  skip.plot.slices = FALSE,
  add = FALSE,
  rescale = TRUE,
  ...
)

Arguments

x

Numeric vector. Values that specify the area of the slices.
labels

Character vector of length length(x). Passed to graphics::text().
radius

Numeric vector. Radious of each slice (can be a scalar).
doughnut

Numeric scalar. Radious of each inner circle (doughnut) (can be a scalar).
origin

Numeric vector of length 2. Coordinates of the origin.
edges

Numeric scalar. Smoothness of the slices curve (can be a vector).
slice.off

Numeric vector. When ⁠!=0⁠, specifies how much to move the slice away from the origin. When scalar is recycled.
init.angle

Numeric scalar. Angle from where to start drawing in degrees.
last.angle

Numeric scalar. Angle where to finish drawing in degrees.
tick.len

Numeric scalar. Size of the tick marks as proportion of the radius.
text.args

List. Further arguments passed to graphics::text().
segments.args

List. Further arguments passed to graphics::segments() when drawing the tickmarks.
skip.plot.slices

Logical scalar. When FALSE, slices are not drawn. This can be useful if, for example, the user only wants to draw the labels.
add

Logical scalar. When TRUE it is added to the current device.
rescale

Logical scalar. When TRUE (default), the y-coordinates of the polygons (slices), text and tickmarks will be rescaled such that the aspectt ratio is preserved, i.e. looks like a circle.
...

Further arguments passed to graphics::polygon() (see details).

Details

The function is a wrapper of graphics::polygon(), so all parameters such as color, density, border, etc. are passed directly by mapply() so that are specified one per slice. The coordinates of the slices are computed internally.

Value

A list with the following elements:

slices

A list of length length(x) with the coordinates of each slice.
textcoords

A numeric matrix of size length(x)*2 with coordinates where the labels can be put at.
alpha0

A numeric vector of size length(x) with the starting degree in radians of the slice.
alpha1

A numeric vector of size length(x) with the ending degree in radians of the slice.

See Also

https://commons.wikimedia.org/wiki/File:Nightingale-mortality.jpg

Examples

# Example 1 -----------------------------------------------------------------
# A set of 3 nested rings rings starting at 315 deg. and ending at 270 deg.

# Values to plot
vals <- c(1,2,3,10)

# Outer (includes labels)
piechart(vals, col=grDevices::blues9[5:8], border=NA, doughnut = .5,
    radius=.75, labels=vals, init.angle = 315, last.angle = 270)

# Middle
piechart(vals, col=grDevices::blues9[3:6], border=NA, doughnut = .3,
    radius=.5, add=TRUE, init.angle = 315, last.angle = 270)

# Inner
piechart(vals, col=grDevices::blues9[1:4], border="gray", doughnut = .1,
    radius=.3, add=TRUE, init.angle = 315, last.angle = 270)

# Example 2 -----------------------------------------------------------------
# Passing values to polygon and playing with the radius and slice.off

piechart(1:10, density=(1:10)^2/2, slice.off = (1:10)/30, doughnut = .5,
  radius = sqrt(10:1),
  # Here we are setting random labels...
  labels=sapply(1:10, function(x) paste(sample(letters, x, TRUE), collapse=""))
  )

Draw segments colored by gradients

Description

Draw segments colored by gradients

Usage

segments_gradient(
  x,
  y = NULL,
  col = colorRamp2(c("transparent", "black"), TRUE),
  lend = 1,
  ...
)

Arguments

x, y

Coordinates passed to grDevices::xy.coords.
col

Color ramp function (see grDevices::colorRamp).
lend

Passed to graphics::segments.
...

Further arguments passed to segments.

Value

See graphics::segments.

Examples

set.seed(1)
x <- cbind(cumsum(rnorm(1e3, sd=.1)), cumsum(rnorm(1e3, sd=.4)))
plot(x, type="n")
segments_gradient(x)

Set/retrieve graphical parameters of a netplot object

Description

Set/retrieve graphical parameters of a netplot object

Usage

set_gpar(x, type, element, idx, ...)

set_edge_gpar(x, element, idx, ...)

set_vertex_gpar(x, element, idx, ...)

get_vertex_gpar(x, element, ..., idx)

get_edge_gpar(x, element, ..., idx)

get_gpar(x, type, element, ..., idx, simplify = TRUE)

Arguments

x

An object of class netplot.
type

Character. Either "edge" or "vertex".
element

Character. If "edge", then it can be either "line" or "arrow", otherwise it can be either "core" or "frame".
idx

(optional) Integer vector. Indices of the elements to be modified. When missing, all elements are modified.
...

Parameters to be modified/retrieved. This is passed to grid::editGrob via grid::gpar.
simplify

Logical. When TRUE it tries to simplify the result. Otherwise it returns a nested list.

Details

set_edge_gpar and set_vertex_gpar are shorthands for set_gpar(type = "edge", ...) and set_gpar(type = "vertex", ...) respectively.

get_edge_gpar and get_vertex_gpar are shorthands for get_gpar(type = "edge", ...) and get_gpar(type = "vertex", ...) respectively.

Value

An object of class netplot with modified parameters.

Examples

library(igraph)
library(netplot)

x <- make_ring(5)

g <- nplot(x)

# Updating edge color
g <- set_edge_gpar(g, col = "gray80")

# Retrieving the color of the vertices (core)
get_vertex_gpar(g, element = "core", "fill", "lwd")