GraphvizAttributes: Graph Attributes for Rgraphviz
Description
The following describes the allowable attributes to be used with
Rgraphviz. Most of these are sent directly to Graphviz and will
influence the plot layout, some of these are only cosmetic and stay in
R. Users are referred to the Graphviz web documentation which
contains some more detailed information on these attributes (and is
our source).
Graph Attributes
General Graph Attributes:
bgcolor:- Color for the entire canvas. The default is
to use
transparent center:- Drawing is centered in the output canvas.
This is a boolean value with a default of
FALSE. fontcolor:- Color used for text, defaulting to
black. fontname:- Font used for text. Default is Times Roman.
fontpath:- Directory used to search for fonts
fontsize:- Font size, in points, for text. This
attribute accepts doubles for values with a default of
14.0
and a minimum value of 1.0 label:- Label for the graph. This is a string with
some extra escape sequences which can be used. The substring
\N is replaced by the name of the node, and the substring
\G by the name of the graph. For graph or cluster
attributes, \G is replaced by the name of the graph or
cluster. For edge attributes, the substring \N is
replaced by the name of the edge, and the substrings \T
and \H by the names of the tail and head nodes. The
default value for nodes is \N with everything else
defaulting to labeljust:- Subgraphs inherit cluster behavior for
labeljust. If
r, the labels are right-justified within
the bounding rectangle. If l they are left-justified.
Otherwise the labels are centered. The default value is
c. labelloc:- Top/bottom placement for graph labels. A
value of
t places the label at the top, b places
them at the bottom. By default root graph labels go on the bottom
and cluster labels go on the top. layers:- Specifies a linearly ordered list of layer
names attached to the graph. Only those components belonging to
the current layer appear. This attribute accepts a
layerList, which is list of strings separated by the
characters defined with the layersep attribute which
defines layer names and implicitly numbered 1,2,etc. The default
is layersep:- Separator characters used to split the
layers into a list of names. The default is colons, tabs or
spaces.
margin:- Set X&Y margins of canvas in inches.
Specified using the notation
val,val where each val is a
double. orientation:- If "[1L*]*", set graph orientation to
landscape. Used only if
rotate is not defined. Default is
the empty string. page:- Width & height of output pages, in inches. If set
and smaller then the size of the layout, a rectangular
array of pages of the specified page size is overlaid on the
layout, with origins aligned in the lower-left corner, thereby
partitioning the layout into pages. The pages are then produced
one at a time in 'pagedir' order. Specified using the notion
val,val where each val is a double. pagedir:- If the
page attribute is set and
applicable, this attribute specifies the order in which the pages
are emitted. This is limited to one of the 8 row or column major
orders. One of BL, BR, TR, RB,
RT, LB, or LT specifying the 8 row or column
major orders for traversing a rectangular array (the first
character corresponding to the major order and the second to the
minor order). The default value is BL quantum:- If 'quantum' > 0.0, node label dimensions
will be rounded to integral multiples of the quantum. This
attribute is of type double, with a default and minimum value of
0.0 ranksep:- In dot, this gives the desired rank
separation in inches. If the value contains
equally, the
centers of all the ranks are spaced equally apart. In twopi,
specifies the separation of concentric circles. This value is of
type double, with a minimum value of 0.02. In dot, the
default value is 0.5 and for twopi it is 1.0. ratio:- Sets the aspect ratio for the drawing. If
numeric, defines aspect ratio. If it is 'fill' and 'size'
has been set, node positions are scaled such that the final
drawing fills exactly the specified size. If 'compress' and the
'size' attribute is set and the graph can not be drawn on a single
page, then the drawing is compressed to fit in the given size. If
'auto', the 'page' attribute is set and the graph cannot be drawn
on a single page, then 'size' is set to an “ideal” value. The
default for this attribute is “fill”
rotate:- If 90, set drawing orientation to landscape.
This attribute accepts integer values and defaults to
0 samplepoints:- If the input graph defines the
'vertices' attribute, and output is dot or xdot, this gives the
number of points used to represent circles and ellipses. It plays
the same role in neato, when adjusting the layout to avoid
overlapping nodes. This attribute accepts integer values and
defaults to
8 size:- Maximum width and height of drawing, in inches.
Specified using the notation
val,val where each val is a
double. If not specified and there is a current output device,
the graph is scaled to fit into that device. If size is
not specified and there is no current output device, a plot region
of the default size will be opened and the graph scaled to match that. start:- Parameter used to determine the initial layout
of nodes. By default, nodes are randomly placed in a
square whose sides have length (number of nodes). The same seed
is always
used for the random number generator, so the initial placement is
repeatable. If 'start' converts to an integer, this is used as a
seed value for the RNG. If 'start' is "regular", the nodes are
placed regularly about a circle. Finally if 'start' is defined,
and not one of those cases, the current time is used to pick a
seed. The default is the empty string.
Dot Only Attributes
clusterrank:- Mode used for handling
clusters. If "local", a subgraph whose name begins with "cluster"
is given special treatment. The subgraph is laid out separately,
and then integrated as a unit into its parent graph. If the cluster has
a 'label' parameter, this label is displayed w/ the cluster.
Acceptable values are
local, global or none -
with local being the default. compound:- Allow edges between clusters. This is a
boolean value with a default of
FALSE concentrate:- Use edge concentrators. This is a
boolean value with a default of
FALSE mclimit:- Scale factor used to alter the 'MinQuit' and
'MaxIter' parameters used during crossing minimization. This is a
double value with a default of
1.0 nodesep:- Minimum space between two adjacent nodes of
the same rank, in inches. This is a double value with a default
of
0.25 and a minimum of 0.02 ordering:- If
out for a graph and n is a node in
G, then edges n->* appear left to right in the order that they
were defined. rankdir:- Determines if the layout is left-to-right or
top-to-bottom. Acceptable values are
LR and TB with
the default being the latter. remincross:- If
TRUE and there are multiple
clusters, run cross minimization a second time. Default is FALSE searchsize:- During network simplex, maximum number of edges
with negative cut values to search when looking for one with
minimum cut value. This is an integer value with a default of
30 showboxes:- Debugging feature for postscript output, R
only. Not currently implemented.
Neato Only Attributes
Damping:- Factor damping force motions. On each
iteration, a node's movement is limited to this factor of its
potential motion. This is a double value with a default of
0.99 and a minimum value of 0.0 defaultdist:- Default distance between nodes in
separate connected components. Only applicable if
pack=FALSE. Defaults to 1+(avg. len)*sqrt(|V|) and
has a minimum value of epsilon. dim:- Set the number of dimensions used for the
layout. This is an integer value with a default and minimum value
of
2. epsilon:- Terminating condition. If length squared of
all energy gradients are less than epsilon, the algorithm stops.
This is a double value with a default of
.0001 times the
number of nodes. maxiter:- Sets the number of iterations used. This is
an integer value with the default of
MAXINT. model:- If
circuit, use circuit resistance model
to compute dissimilarity values, otherwise use shortest path.
Defaults to the empty string.
Twopi Only Attributes
root:- Name of the node to use as the center of the
layout. If not defined, will pick the most central node.
Not Dot Attributes
normalize:- Normalize coordinates of final layout so
that the first point is at the origin, then rotate so that the
first edge is horizontal. This is a boolean value with a default
of
FALSE. overlap:- If
scale, remove node overlaps by
scaling. If FALSE, use Voronoi technique, otherwise leave
overlaps. Default is the empty string. pack:- If "true" or non-negative integer - each
connected component is laid out separately and then the graphs
are packed tightly. If pack has an integral value, this is used
as the size (in points) of a margin around each part; otherwise
a default margin of 8 is used. If 'false', the entire graph is
laid out together. For twopi layouts, this just sets the
margin. Default is
FALSE packmode:- Indicates the granularity and method used
for packing. This will automatically turn on
pack.
Acceptable values are node, clust and graph,
specifying the granularity of packing connected components when
pack=TRUE. The default is node. sep:- Fraction to increase polygons for purposes of
determining overlap. This is a double value with a default of
0.01. splines:- Draw edges as splines. This is a boolean
value with a default of
TRUE. voro_margin:- Factor to scale up drawing to allow
margin for expansion in Voronoi technique. This is a double value
with a default of
0.05 and a minimum value of 0.0
Output Based
resolution:- Number of pixels per inch on a display,
used for SVG output. The default for this attribute is
0.96 and it accepts values of type double. stylesheet:- A URL or pathname specifying a XML style
sheet, for SVG output.
truecolor:- Output relies on a truecolor color model,
used with bitmap outputs. This is a boolean value with a default
of
FALSE
Misc
URL:- Hyperlink incorporated into the output. For
whole graphs, used as part of an image map. Not currently implemented
comment:- A device dependent commentary. Not currently
implemented.
nslimit:- Number of iterations in network simplex
applications. Used in computing node x coordinates
nslimit1:- Same as
nslimit but for ranking
nodes outputorder:- Specify order in which nodes and edges are
drawn. R only
Edge Attributes
General Edge Attributes
arrowhead:- Shape of the arrowhead. Currently somewhat
limited in what can be rendered in R as opposed to what is
available via Graphviz in that only
open and none
are allowed. The open is used by default for directed
edges and none for undirected edges. R only(?) arrowsize:- Multiplicative scale factor for arrowheads,
type double. R only (?). This attribute accepts values of type
double with a default of
1.0 and minimum of 1.0. arrowtail:- Style of arrow on the tail node of an edge,
see
arrowhead. For directed edges that with bidirectional
arrows, open is used. R only(?) color:- The color of the edge. Defaults to
black. decorate:- If TRUE, attach edge label to edge by a
2-segment polyline, underlining the label, then going to the
closest point of the spline. Default is
FALSE. Currently
unimplemented. dir:- Edge type drawing, which ends should get the
arrowhead. R only(?). For directed graphs, this defaults to
forward and undirected graphs default to both.
Other possible values are both (arrows in both
directions) and back (Arrow on the tail only) fontcolor:- The color used for text. The
default value is
black in R fontname:- Font used for text. Defaults to Times
Roman. Currently unimplemented.
fontsize:- Font size, used for text. Defaults to
14.0 with a minimum value of 1.0 headclip:- Head of the edge is clipped to the boundary
of the head node, otherwise it goes to the center of the node.
This is a boolean value with the default of
TRUE.
Currently unimplemented headlabel:- Label for the head of the edge. See
label in Graph Attributes for a description of
additional escape sequences. Currently unimplemented. headport:- Where on the node to aim the edges, uses
center,
n, s, e, nw, nw, se, and
sw. The default is center. label:- The edge label. See
label in Graph Attributes for a description of
additional escape sequences. labelangle:- Angle in degrees that the label is
rotated, as a double. Default is
-25.0 with a minimum
value of -180.0. Currently unimplemented. labeldistance:- Multiplicative scaling factor adjusting
the distance that the label is from the node. This is a double
value with a default of
1.0 and a minimum value of 0.0. layer:- Specifies the layers that this edge is present,
type of
layerRange. This is specified as a string in the
format layerID or layerIDslayerIDslayerID..., where
s is a character from the layersep attribute. The
layerID attribute can be all, a decimal integer or a
layer name. Defaults to the empty string. style:- Set line style for the edge. R only. Can be
one of
dashed, dotted, solid, invis
and bold. Defaults to solid. tailclip:- Same as
headclip except for the tail
of the edge. Defaults to TRUE. Currently unimplemented. taillabel:- Same as
headlabel except for the
tail of the edge. Defaults to the empty string. Currently
unimplemented. weight:- The weight of the edge. This attribute is of
type double with a default of
0.75 and a minimum value of
0.01.
Dot Only Attributes
constraint:- If FALSE, edge is not used in ranking
nodes. Default is
TRUE. lhead:- Logical head of an edge. If
compound is
TRUE, if lhead is defined and is the name of a cluster
containing the real head, then the edge is clipped to the boundary
of the cluster. ltail:- Same as
lhead but for the tail of the
edge minlen:- Minimum edge length (rank difference between
head and tail). This is an integer value with a default of
1 and a minimum of 0. samehead:- Edges with the same head and
samehead
value are aimed at the same point on the head node. sametail:- Same as
samehead but for the tail of
the edge.
Neato Only Attributes
len:- Preferred edge length, in inches. This attribute
accepts double values with a default of
1.0.
Misc
URL:- Hyperlink incorporated into the output. Not
currently supported
headURL:- URL for the head of the edge. Not currently supported
headtooltip:- If there's a headURL, annotation for a
tooltip. R only, not currently supported
tailURL:- Same as
headURL but for the tail of an
edge tailtooltip:- Same as
headtooltip but for the
head of an edge tooltip:- Same as
headtooltip but for the edge
in general showboxes:- Debugging feature for postscript. Not
currently supported
comment:- Device dependent comment inserted into the
output. Not currently supported
Node Attributes
General Node Attributes
color:- Basic drawing color for the node, corresponding
to the outside edge of the node. The interior of the node is
specified with the
fillcolor attribute. Defaults to
black. distortion:- Distortion factor for
shape=polygon, positive values cause top to be larger then
bottom, negative is opposite. This is a double value with a
default of 0.0 and a minimum value of -100.0 fillcolor:- Background color of the node. This
defaults to
black. fixedsize:- Use only
width and height
attributes, do not expand for the width of the label. This
defaults to TRUE. fontcolor:- Color used for text. This
defaults to
black. fontname:- Font used for text. The default of this is
Times Roman.
fontsize:- Size of font for the text. This defaults to
14.0 with a minimum size of 1.0. height:- Height of the node, in inches. This attribute
accepts values as doubles with a default of
0.5 and a minimum
value of 0.02. label:- Label for the node. See
label in
Graph Attributes for an explanation of extra escape sequences. layer:- Layers in which the node is present. See
layer in Edge Attributes for an explanation of
acceptable inputs. peripheries:- Set number of peripheries used in
polygonal shapes and cluster boundaries. Note that user-defined
shapes are treated as a form box shape, so the default peripheries
value is 1 and the user-defined shape will be drawn in a bounding
rectangle. Setting peripheries=0 will turn this off. Also, 1 is
the maximum peripheries value for clusters. Not currently
implemented.
pos:- Position of the node (For neato layouts, this is
the initial position of the node). Specified using the notion
val,val where each val is a double. regular:- Force the polygon to be regular. Defaults to
FALSE. shape:- The shape of the node. Current acceptable
values are
circle, rectangle, rect,
box and ellipse. The circle shape is the
default. Note that box, rect and rectangle
all correspond to the same actual shape. sides:- Number of sides if
shape=polygon. This
is an integer value with a default value of 4 and a minimum
value of 0. skew:- Skew factor for
shape=polygon. Positive
values skew the polygon to the right, negative to the left. This
is a double value with a default value of 0.0 and a minimum
value of -100.0. style:- Set style for the node boundary. R only. Can be
one of
dashed, dotted, solid, invis
and bold. Defaults to solid. width:- Width of the node, in inches. Default is
0.75 with a minimum value of 0.01
Dot Only Attributes
group:- If the end points of an edge belong to the same
group, ie they have the same group attributes, parameters are set
to avoid crossings and keep the edges straight
Neato Only Attributes
pin:- If TRUE and node has a
pos attribute on
input, neato prevents the node from moving from the input
position. The default for this attribute is FALSE.
Misc
tooltip:- Annotated tooltip if URL exists. R only.
Currently unsupported
toplabel:- Label near the top of nodes of shape M*.
Currently unsupported
URL:- Hyperlink incorporated into the output. Not
currently supported
bottomlabel:- Same as
toplabel but for the
bottom of the node comment:- Device dependent comment inserted into the
output. Not currently supported
shapefill:- If non-empty, if output is ps or svg and
shape is 'espf', taken as a filename containing a device-dependent
description of a node's shape. If non-empty for bitmap output
(gif, jpg, etc), and shape set to 'custom', taken as the URL for a
file containing the bitmap image for the node. For files on the
local machine, the URL begins with "file://". For remote files,
graphviz must have been configured to use a command such as curl
to retrieve the files remotely. Currently unsupported
z:- Provides z coordinates for the node in a 3D system.
Currently unsupported
details
Different attributes are appropriate for different specific graph
layout algorithms. Graphviz supports three different layout
algorithms, dot, neato and twopi. There is some tension between attributes that graphviz supports and
those that we can support at the R level. Please let us know if there
are situations that are not being handled appropriately. All attributes are passed down to graphviz. However they can be later
modified for rendering in R.