plotweb {diagram}R Documentation

plots a web

Description

plots a web, based on a flow matrix

Usage

plotweb(flowmat, names=NULL, lab.size=1.5, add=FALSE, fig.size=1.3, 
  main="", sub="", sub2="", log=FALSE, mar=c(2,2,2,2),
  nullflow=NULL, minflow=NULL, maxflow=NULL,legend=TRUE,
  leg.digit=5, leg.title=NULL, lcol="black", arr.col="black",
  val=FALSE, val.digit=5, val.size=0.6, val.col="red",
  val.title=NULL, val.ncol=1, budget=FALSE, bud.digit=5, bud.size=0.6,
  bud.title="budget", bud.ncol=1, maxarrow=10, minarrow=1, length=0.1,
  dcirc=1.2, bty="o", ...)

Arguments

flowmat flow matrix, rows=flow *from*, columns=flow *to*.
names string vector with the names of components.
lab.size relative size of name label text.
add start a new plot (FALSE), or add to current (TRUE).
fig.size if add = FALSE: relative size of figure.
main if add = FALSE: main title.
sub if add = FALSE: sub title.
sub2 ifadd = FALSE: title in bottom.
log logical indicating whether to scale the flow values logarithmically.
mar the figure margins.
nullflow either one value or a two-valued vector; if flow < nullflow[1] or flow > nullflow[2] (if two values): flow is assumed = 0 and the arrow is not drawn.
minflow flowvalue corresponding to minimum arrow thickness.
maxflow flowvalue corresponding to maximum arrow thickness.
legend logical indicating whether to add a legend with arrow thickness.
leg.digit nr of digits for writing legend - only if legend = TRUE.
leg.title title for arrow legend, e.g to give units - only if legend =TRUE.
lcol line color of arrow - not used.
arr.col arrow color. One value or a matrix, with same dimensions as flowmat; if a matrix, each arrow can have a different color.
val logical indicating whether to write flow values as a legend.
val.digit nr of digits for writing values - only if val =TRUE.
val.size relative size for writing values - only if val =TRUE.
val.col color for writing values - only if val =TRUE.
val.title title for values legend - only if val =TRUE.
val.ncol number of columns for writing values - only if val =TRUE.
budget logical indicating whether to calculate budget (sum of flows in - sum of flows out) per component.
bud.digit nr of digits for writing budget - only if budget =TRUE.
bud.size relative size for writing budget - only if budget =TRUE.
bud.title title for budget legend - only if budget =TRUE.
bud.ncol number of columns for writing budget - only if budget =TRUE.
maxarrow maximal thickness of arrow.
minarrow minimal thickness of arrow.
length length of the edges of the arrow head (in inches).
dcirc if cannibalism (flow from i to i), offset of circular 'arrow' - if dcirc = 0:no circle drawn.
bty the type of box to be drawn around the legends (legend, val, budget). The allowed values are "o" (the default) and "n".
... extra arguments passed to R-function arrows.

Details

This function is less flexible than function plotmat

It is meant for visualisation of food web flows, that are inputted as a flow matrix.

It displays the elements on a circle, and, where there is a mass flow, two elements are connected,

the magnitude of the web flows is reflected by the thickness of the arrow

Note that the input matrices from function plotmat and plotweb are transposed.

Author(s)

Karline Soetaert <k.soetaert@nioo.knaw.nl>

See Also

plotmat,

Rigaweb, Takapotoweb

try: demo(plotweb)

Examples

  plotweb(Rigaweb,main="Gulf of Riga food web",sub="mgC/m3/d",val=TRUE)

  ArrCol <- Rigaweb
  ArrCol[] <- "black"
  ArrCol[,"Sedimentation"] <- "green"

  plotweb(Rigaweb,main="Gulf of Riga food web",sub="mgC/m3/d",val=FALSE,
          arr.col=ArrCol)

  plotweb(diag(20),main="plotweb")

[Package diagram version 1.4 Index]