fan.plot {plotrix}

Display a fan plot

Description

Displays numerical values as the arcs of overlapping sectors.

Usage

 fan.plot(x,edges=200,radius=1,col=NULL,align.at=NULL,max.span=NULL,
  labels=NULL,labelpos=NULL,label.radius=1.2,align="left",shrink=0.02,
  main="",ticks=NULL,include.sumx=FALSE,...)

Arguments

x

Vector of numbers.

edges

The number of edges with which to draw a circle.

radius

The radius of the sectors.

col

The colors with which to fill the sectors.

align.at

Where to align the sectors (see Details).

max.span

The angle of the maximal sector in radians. The default is to scale ‘⁠x⁠’ so that it sums to 2*pi.

labels

Labels placed around the sector arcs.

labelpos

Optional circumferential positions for the labels.

label.radius

How far away from the sectors the labels will be placed. May be a vector with a radius for each label.

align

Position of the alignment of sectors (see Details).

shrink

How much to shrink each successive sector in user units.

main

Optional title for the plot.

ticks

The number of ticks that would appear if the sectors were on a pie chart. Default is no ticks, TRUE gives the number of ticks equal to the integer sum of ‘⁠x⁠’, which is fairly sensible if ‘⁠x⁠’ is a vector of integers.

include.sumx

Whether to include the sum of all ‘⁠x⁠’ values as the largest sector.

...

Additional arguments passed to ‘⁠polygon⁠’.

Details

‘⁠fan.plot⁠’ displays sectors much like a pie chart except that the sectors are overlapped. this allows the angular extents of the sectors to be visually compared much more accurately by the viewer. Sectors are plotted from the largest to the smallest, shrinking the radius of each successive sector.

When sending output to the postscript device, the resulting image can be trimmed by changing the values in BoundingBox in the header with a text editor.

Value

The circumferential positions of the labels in radians. These are returned in order of decreasing size of the values plotted.

Author(s)

Jim Lemon, Anupam Tyagi

Examples

 iucn.df<-data.frame(area=c("Africa","Asia","Europe","N&C America",
  "S America","Oceania"),threatened=c(5994,7737,1987,4716,5097,2093))
 fan.plot(iucn.df$threatened,max.span=pi,
  labels=paste(iucn.df$area,iucn.df$threatened,sep="-"),
  main="Threatened species by geographical area (fan.plot)",ticks=276)