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 <karline.soetaert@nioz.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")