DOT(1)									DOT(1)



NAME
       dot - filter for drawing directed graphs
       neato - filter for drawing undirected graphs
       twopi - filter for radial layouts of graphs
       circo - filter for circular layout of graphs
       fdp - filter for drawing undirected graphs
       sfdp - filter for drawing large undirected graphs
       patchwork - filter for tree maps

SYNOPSIS
       dot [options] [files]
       neato [options] [files]
       twopi [options] [files]
       circle [options] [files]
       fdp [options] [files]
       sfdp [options] [files]
       patchwork [options] [files]

DESCRIPTION
       These  are a collection of programs for drawing graphs.	There is actu-
       ally only one main program; the specific layout algorithms  implemented
       as  plugins.  Thus,  they  largely  share  all of the same command-line
       options.	 dot draws directed graphs.  It works well on DAGs  and	 other
       graphs that can be drawn as hierarchies.

       neato  draws  undirected graphs using ''spring'' models (see Kamada and
       Kawai, Information Processing Letters 31:1, April 1989).

       twopi draws graphs using a radial layout (see G.	 Wills,	 Symposium  on
       Graph  Drawing  GD'97, September, 1997).	 Basically, one node is chosen
       as the center and put at the origin.  The remaining nodes are placed on
       a  sequence  of	concentric  circles  centered about the origin, each a
       fixed radial distance from the previous circle.	All nodes  distance  1
       from  the  center  are placed on the first circle; all nodes distance 1
       from a node on the first circle are placed on the second circle; and so
       forth.

       circo  draws graphs using a circular layout (see Six and Tollis, GD '99
       and ALENEX '99, and Kaufmann and Wiese, GD '02.)	 The  tool  identifies
       biconnected  components	and draws the nodes of the component on a cir-
       cle. The block-cutpoint tree is then laid out using a recursive	radial
       algorithm.  Edge	 crossings within a circle are minimized by placing as
       many edges on the circle's perimeter as possible.   In  particular,  if
       the  component is outerplanar, the component will have a planar layout.

       If a node belongs to multiple non-trivial biconnected  components,  the
       layout  puts  the  node	in  one of them. By default, this is the first
       non-trivial component found in the search from the root component.

       fdp draws undirected graphs using a ''spring'' model. It	 relies	 on  a
       force-directed  approach in the spirit of Fruchterman and Reingold (cf.
       Software-Practice & Experience 21(11), 1991, pp. 1129-1164).

       sfdp also draws undirected graphs using the ''spring'' model  described
       above,  but  it uses a multi-scale approach to produce layouts of large
       graphs in a reasonably short time.

       patchwork draws the graph as a squarified treemap (see M. Bruls et al.,
       "Squarified  treemaps", Proc. Joint Eurographics and IEEE TCVG Symp. on
       Visualization, 2000, pp. 33-42). The clusters of the graph are used  to
       specify the tree.

OUTPUT FORMATS
       Graphviz	 uses an extensible plugin mechanism for its output renderers,
       so to see what output formats your installation of dot supports you can
       use ''dot -Txxx'' (where xxx is an unlikely format) and check the warn-
       ing message.  Also, The plugin mechanism supports multiple  implementa-
       tions  of the output formats.  To see what variants are available, use,
       for example: ''dot -Tpng:'' and to force a particular variant, use, for
       example: ''dot -Tpng:gd''

       Traditionally, Graphviz supports the following:
       -Tps (PostScript),
       -Tsvg -Tsvgz (Structured Vector Graphics),
       -Tfig (XFIG graphics),
       -Tpng -Tgif (bitmap graphics),
       -Timap (imagemap files for httpd servers for each node or edge that has
       a non-null "href" attribute.),
       -Tcmapx (client-side imagemap for use in html and xhtml).
       Additional less common or more special-purpose output  formats  can  be
       found at //http://www.graphviz.org/content/output-formats.

       Alternative  plugins providing support for a given output format can be
       found from the error message resulting from appending a ':' to the for-
       mat. e.g. -Tpng: The first plugin listed is always the default.

       The  -P	switch	can  be used to produce a graph of all output variants
       supported by plugins in the local installation of graphviz.

GRAPH FILE LANGUAGE
       Here is a synopsis of the  graph	 file  language,  normally  using  the
       extension .gv, for graphs:

       [strict] (graph|digraph) name { statement-list }
       is the top-level graph. If the graph is strict, then multiple edges are
       not allowed between the same pairs of  nodes.   If  it  is  a  directed
       graph,  indicated by digraph, then the edgeop must be "->". If it is an
       undirected graph then the edgeop must be "--".

       Statements may be:

       name=val;
       node [name=val];
       edge [name=val];
       Set default graph, node, or edge attribute name to val.	Any  subgraph,
       node, or edge appearing after this inherits the new default attributes.

       n0 [name0=val0,name1=val1,...]; Creates node n0 (if it does not already
       exist) and sets its attributes according to the optional list.

       n0 edgeop n1 edgeop ... edgeop nn [name0=val0,name1=val1,...];
       Creates	edges  between nodes n0, n1, ..., nn and sets their attributes
       according to the optional list.	Creates nodes as necessary.

       [subgraph name] { statement-list }
       Creates a subgraph.  Subgraphs may be used in place of n0, ...,	nn  in
       the  above statements to create edges.  [subgraph name] is optional; if
       missing, the subgraph is assigned an internal name.

       Comments may be /*C-like*/ or //C++-like.


       Attribute names and values are ordinary (C-style) strings.  The follow-
       ing sections describe attributes that control graph layout.

       A   more	  complete  description	 of  the  language  can	 be  found  at
       http://www.graphviz.org/content/dot-language.

GRAPH, NODE AND EDGE ATTRIBUTES
       Graphviz uses the name=value attributes, attached to graphs, subgraphs,
       nodes  and  edges, to tailor the layout and rendering. We list the more
       prominent  attributes  below.  The  complete  list  is	available   at
       http://www.graphviz.org/content/attrs.

  Graph Attributes
       size="x,y" specifies the maximum bounding box of drawing in inches.

       ratio=f	sets  the aspect ratio to f which may be a floating point num-
       ber, or one of the keywords fill, compress, or auto.

       layout=engine indicates the preferred layout  engine  ("dot",  "neato",
       fdp"  etc)  overriding  the default from the basename of the command or
       the -K commandline option.

       margin=f sets the page margin (included in the page size).

       nodesep=f sets the minimum separation between nodes.

       ranksep=f sets the minimum separation between ranks.

       ordering=out constrains order of out-edges in a subgraph	 according  to
       their file sequence.

       rankdir=LR|RL|BT	 requests  a  left-to-right,  right-to-left,  or  bot-
       tom-to-top, drawing.

       rank=same (or min or max) in a subgraph constrains the rank  assignment
       of  its nodes.	If a subgraph's name has the prefix cluster, its nodes
       are drawn in a distinct rectangle  of  the  layout.   Clusters  may  be
       nested.

       rotate=90  sets landscape mode.	(orientation=land is backward compati-
       ble but obsolete.)

       center=n a non-zero value centers the drawing on the page.

       color=colorvalue sets foreground color (bgcolor for background).

       href="url" the default url for image map files;	in  PostScript	files,
       the  base URL for all relative URLs, as recognized by Acrobat Distiller
       3.0 and up.

       URL="url" ("URL" is a synonym for "href".)

       stylesheet="file.css" includes a reference to a stylesheet in -Tsvg and
       -Tsvgz outputs.	Ignored by other formats.

       splines	If  set	 to true, edges are drawn as splines.  If set to poly-
       line, edges are drawn as polylines.  If set to ortho, edges  are	 drawn
       as  orthogonal  polylines.   In	all  of these cases, the nodes may not
       overlap.	 If splines=false or splines=line, edges  are  drawn  as  line
       segments.   The	default	 is true for dot, and false for all other lay-
       outs.


       (neato-specific attributes)
       start=val.  Requests random initial placement and seeds the random num-
       ber  generator.	 If  val  is not an integer, the process ID or current
       time is used as the seed.

       epsilon=n.  Sets the cutoff for the solver.  The default is 0.1.


       (twopi-specific attributes)
       root=ctr. This specifies the node to be used as the center of the  lay-
       out.  If	 not specified, twopi will randomly pick one of the nodes that
       are furthest from a leaf node, where a leaf node is a node of degree 1.
       If no leaf nodes exists, an arbitrary node is picked as center.

       ranksep=val.  Specifies	the  radial  distance  in  inches  between the
       sequence of rings. The default is 0.75.

       overlap=mode. This specifies what twopi should do if any nodes overlap.
       If  mode	 is  "false",  the program uses Voronoi diagrams to adjust the
       nodes to eliminate overlaps. If mode is "scale",	 the  layout  is  uni-
       formly scaled up, preserving node sizes, until nodes no longer overlap.
       The latter technique removes overlaps  while  preserving	 symmetry  and
       structure,  while  the  former  removes	overlaps  more	compactly  but
       destroys symmetries.  If mode is "true" (the default), no repositioning
       is done.


       (circo-specific attributes)
       root=nodename.  Specifies  the  name  of	 a  node occurring in the root
       block. If the graph is disconnected, the root  node  attribute  can  be
       used to specify additional root blocks.

       mindist=value.  Sets  the  minimum separation between all nodes. If not
       specified then circo uses a default value of 1.0.


       (fdp-specific attributes)
       K=val. Sets the default ideal node separation in the layout.

       maxiter=val. Sets the maximum number of iterations used to  layout  the
       graph.

       start=val. Adjusts the random initial placement of nodes with no speci-
       fied position.  If val is is an integer, it is used as the seed for the
       random  number  generator.   If	val  is	 not an integer, a random sys-
       tem-generated integer, such as the process ID or current time, is  used
       as the seed.



  Node Attributes
       height=d	 or  width=d  sets  minimum  height  or	 width.	 Adding fixed-
       size=true forces these to be the actual size (text labels are ignored).

       shape=record polygon epsf builtin_shape
       builtin_polygon	can  be plaintext ellipse oval circle egg triangle box
       diamond trapezium parallelogram house hexagon octagon  note  tab	 box3d
       component, among others.	 (Polygons are defined or modified by the fol-
       lowing node attributes: regular, peripheries, sides, orientation,  dis-
       tortion	and  skew.)   epsf  uses the node's shapefile attribute as the
       path name of an external EPSF file to be automatically loaded  for  the
       node shape.

       See http://www.graphviz.org/content/node-shapes for a complete descrip-
       tion of node shapes.

       label=text where text may include escaped newlines \n, \l,  or  \r  for
       center, left, and right justified lines.	 The string '\N' value will be
       replaced by the node name.  The string '\G' value will be  replaced  by
       the  graph  name.  Record labels may contain recursive box lists delim-
       ited by { | }.  Port identifiers in labels are set off by angle	brack-
       ets < >.	 In the graph file, use colon (such as, node0:port28).

       Graphviz	 also  supports special HTML-like labels for constructing com-
       plex  node  content.  A	full-description  of   these   is   given   at
       http://www.graphviz.org/content/node-shapes#html.

       fontsize=n sets the label type size to n points.

       fontname=name sets the label font family name.

       color=colorvalue	 sets the outline color, and the default fill color if
       style=filled and fillcolor is not specified.

       fillcolor=colorvalue sets the fill color	 when  style=filled.   If  not
       specified,  the	fillcolor when style=filled defaults to be the same as
       the outline color.

       fontcolor=colorvalue sets the label text color.

       A colorvalue may be  "h,s,v"  (hue,  saturation,	 brightness)  floating
       point numbers between 0 and 1, or an X11 color name such as white black
       red green blue yellow magenta cyan or burlywood, or a  "#rrggbb"	 (red,
       green, blue, 2 hex characters each) value.

       style=filled solid dashed dotted bold invis or any Postscript code.

       href="url"  sets	 the  url for the node in imagemap, PostScript and SVG
       files.  The substrings '\N' and '\G' are substituted in the same manner
       as  for	the  node label attribute.  Additionally the substring '\L' is
       substituted with the node label string.

       URL="url" ("URL" is a synonym for "href".)

       target="target" is a target string for client-side imagemaps  and  SVG,
       effective  when	nodes have a URL.  The target string is used to deter-
       mine which window of the browser is used for the URL.   Setting	it  to
       "_graphviz"  will  open	a  new	window if it doesn't already exist, or
       reuse it if it does.  If the target string is empty, the default,  then
       no target attribute is included in the output.  The substrings '\N' and
       '\G' are	 substituted  in  the  same  manner  as	 for  the  node	 label
       attribute.   Additionally  the  substring  '\L' is substituted with the
       node label string.

       tooltip="tooltip" is a tooltip string  for  client-side	imagemaps  and
       SVG,  effective	when nodes have a URL.	The tooltip string defaults to
       be the same as the label string, but this attribute permits nodes with-
       out  labels  to still have tooltips thus permitting denser graphs.  The
       substrings '\N' and '\G' are substituted in the same manner as for  the
       node  label  attribute.	Additionally the substring '\L' is substituted
       with the node label string.

       The following attributes apply only to polygon shape nodes:

       regular=n if n is non-zero then the polygon is made regular, i.e.  sym-
       metric  about  the  x  and  y  axis, otherwise the polygon takes on the
       aspect ratio of the label.  builtin_polygons that are not already regu-
       lar  are	 made  regular	by  this attribute.  builtin_polygons that are
       already regular are not affected (i.e.  they cannot  be	made  asymmet-
       ric).

       peripheries=n sets the number of periphery lines drawn around the poly-
       gon.   This  value  supersedes  the  number  of	periphery   lines   of
       builtin_polygons.

       sides=n	sets  the  number  of  sides to the polygon. n<3 results in an
       ellipse.	 This attribute is ignored by builtin_polygons.

       orientation=f sets the orientation of the first	apex  of  the  polygon
       counterclockwise	 from  the  vertical, in degrees.  f may be a floating
       point number.  The orientation  of  labels  is  not  affected  by  this
       attribute.   This  attribute  is	 added	to  the initial orientation of
       builtin_polygons.

       distortion=f sets the amount of broadening of the top and narrowing  of
       the  bottom  of	the  polygon  (relative to its orientation).  Floating
       point values between -1	and  +1	 are  suggested.   This	 attribute  is
       ignored by builtin_polygons.

       skew=f  sets  the amount of right-displacement of the top and left-dis-
       placement of the bottom of the polygon (relative to  its	 orientation).
       Floating	 point values between -1 and +1 are suggested.	This attribute
       is ignored by builtin_polygons.


       (circo-specific attributes)
       root=true/false. This specifies that the	 block	containing  the	 given
       node be treated as the root of the spanning tree in the layout.


       (fdp-specific attributes)
       pin=val.	 If  val  is "true", the node will remain at its initial posi-
       tion.


  Edge Attributes
       minlen=n where n is an integer factor that applies to the  edge	length
       (ranks for normal edges, or minimum node separation for flat edges).

       weight=n	 where n is the integer cost of the edge.  Values greater than
       1 tend to shorten the edge.  Weight 0 flat edges are ignored for order-
       ing nodes.

       label=text  where  text	may include escaped newlines \n, \l, or \r for
       centered, left, or right justified lines.  If  the  substring  '\T'  is
       found  in  a  label  it will be replaced by the tail_node name.	If the
       substring '\H' is found in a label it will be replaced by the head_node
       name.   If  the	substring  '\E'	 value	is found in a label it will be
       replaced by: tail_node_name->head_node_name If the  substring  '\G'  is
       found  in  a  label  it	will  be  replaced  by the graph name.	or by:
       tail_node_name--head_node_name for undirected graphs.

       fontsize=n sets the label type size to n points.

       fontname=name sets the label font family name.

       fontcolor=colorvalue sets the label text color.

       style=solid dashed dotted bold invis

       color=colorvalue sets the line color for edges.

       color=colorvaluelist a ':' separated list of colorvalue creates	paral-
       lel edges, one edge for each color.

       dir=forward back both none controls arrow direction.

       tailclip,headclip=false disables endpoint shape clipping.

       href="url"  sets	 the  url for the node in imagemap, PostScript and SVG
       files.  The substrings '\T', '\H', '\E' and '\G' are substituted in the
       same  manner  as	 for  the edge label attribute.	 Additionally the sub-
       string '\L' is substituted with the edge label string.

       URL="url" ("URL" is a synonym for "href".)

       target="target" is a target string for client-side imagemaps  and  SVG,
       effective  when	edges  have a URL.  If the target string is empty, the
       default, then no target attribute is included in the output.  The  sub-
       strings '\T', '\H', '\E' and '\G' are substituted in the same manner as
       for the edge label attribute.  Additionally the substring '\L' is  sub-
       stituted with the edge label string.

       tooltip="tooltip"  is a tooltip string for client-side imagemaps effec-
       tive when edges have a URL.  The tooltip string defaults to be the same
       as the edge label string.  The substrings '\T', '\H', '\E' and '\G' are
       substituted in the same manner as for the edge label attribute.	 Addi-
       tionally	 the substring '\L' is substituted with the edge label string.

       arrowhead,arrowtail=none, normal, inv, dot, odot, invdot, invodot, tee,
       empty, invempty, open, halfopen, diamond, odiamond, box, obox, crow.

       arrowsize				 (norm_length=10,norm_width=5,
       inv_length=6,inv_width=7,dot_radius=2)

       headlabel,taillabel=string for port labels.   labelfontcolor,labelfont-
       name,labelfontsize  for	head  and  tail	 labels.  The substrings '\T',
       '\H', '\E' and '\G' are substituted in the same manner as for the  edge
       label  attribute.   Additionally the substring '\L' is substituted with
       the edge label string.

       headhref="url" sets the url for the head port in	 imagemap,  PostScript
       and  SVG	 files.	  The substrings '\T', '\H', '\E' and '\G' are substi-
       tuted in the same manner as for the edge label attribute.  Additionally
       the substring '\L' is substituted with the edge label string.

       headURL="url" ("headURL" is a synonym for "headhref".)

       headtarget="headtarget"	is  a  target string for client-side imagemaps
       and SVG, effective when edge heads have a URL.  The  headtarget	string
       is  used	 to determine which window of the browser is used for the URL.
       If the  headtarget  string  is  empty,  the  default,  then  headtarget
       defaults	 to  the  same	value  as target for the edge.	The substrings
       '\T', '\H', '\E' and '\G' are substituted in the same manner as for the
       edge  label  attribute.	Additionally the substring '\L' is substituted
       with the edge label string.

       headtooltip="tooltip" is a tooltip  string  for	client-side  imagemaps
       effective  when	head ports have a URL.	The tooltip string defaults to
       be the same as the headlabel string.  The substrings  '\T',  '\H',  and
       '\E'  are  substituted  in  the	same  manner  as  for  the  edge label
       attribute.  Additionally the substring '\L'  is	substituted  with  the
       edge label string.

       tailhref="url"  sets  the url for the tail port in imagemap, PostScript
       and SVG files.  The substrings '\T', '\H', '\E' and  '\G'  are  substi-
       tuted in the same manner as for the edge label attribute.  Additionally
       the substring '\L' is substituted with the edge label string.

       tailURL="url" ("tailURL" is a synonym for "tailhref".)

       tailtarget="tailtarget" is a target string  for	client-side  imagemaps
       and  SVG,  effective when edge tails have a URL.	 The tailtarget string
       is used to determine which window of the browser is used for  the  URL.
       If  the	tailtarget  string  is	empty,	the  default,  then tailtarget
       defaults to the same value as target  for  the  edge.   The  substrings
       '\T', '\H', '\E' and '\G' are substituted in the same manner as for the
       edge label attribute.  Additionally the substring '\L'  is  substituted
       with the edge label string.

       tailtooltip="tooltip"  is  a  tooltip  string for client-side imagemaps
       effective when tail ports have a URL.  The tooltip string  defaults  to
       be  the	same as the taillabel string.  The substrings '\T', '\H', '\E'
       and '\G' are substituted in the same  manner  as	 for  the  edge	 label
       attribute.   Additionally  the  substring  '\L' is substituted with the
       edge label string.

       labeldistance and labelangle (in degrees CCW) specify the placement  of
       head and tail labels.

       decorate draws line from edge to label.

       samehead,sametail  aim  edges  having  the same value to the same port,
       using the average landing point.

       constraint=false causes an edge to be ignored for rank assignment.

       layer=id or id:id or "all" sets the edge's active  layers.   The	 empty
       string means no layers (invisible).


       (neato-specific attributes)
       w=f  sets the weight (spring constant) of an edge to the given floating
       point value.  The default is 1.0; greater values	 make  the  edge  tend
       more toward its optimal length.

       len=f sets the optimal length of an edge.  The default is 1.0.

       (fdp-specific attributes)
       weight=f	 sets the weight of an edge to the given floating point value.
       The default is 1.0; greater values make the edge tend more  toward  its
       optimal length.

COMMAND-LINE OPTIONS
       -G sets a default graph attribute.
       -N sets a default node attribute.
       -E  sets	 a  default edge attribute.  Example: -Gsize="7,8" -Nshape=box
       -Efontsize=8

       -lfile loads custom PostScript library  files.	Usually	 these	define
       custom  shapes  or  styles.   If	 -l  is	 given by itself, the standard
       library is omitted.

       -Tlang sets the output language as described above.


       -n[1|2] (no-op) If set, neato assumes nodes  have  already  been	 posi-
       tioned  and  all	 nodes	have a pos attribute giving the positions.  It
       then performs an	 optional  adjustment  to  remove  node-node  overlap,
       depending on the value of the overlap attribute, computes the edge lay-
       outs, depending on the value of the splines attribute,  and  emits  the
       graph  in  the  appropriate  format.  If num is supplied, the following
       actions occur:
	   num = 1
       Equivalent to -n.
	   num > 1
       Use node positions as specified, with no adjustment to remove node-node
       overlaps,  and  use  any	 edge  layouts	already	 specified  by the pos
       attribute.  neato computes an edge layout for any edge  that  does  not
       have  a	pos attribute.	As usual, edge layout is guided by the splines
       attribute.

       -Klayout override the default layout  engine  implied  by  the  command
       name.

       -O  automatically generate output filenames based on the input filename
       and the -T format.

       -P generate a graph of the currently available plugins.

       -v (verbose) prints various information useful for debugging.

       -c configure plugins.

       -m memory test (observe no growth with top, kill when done).

       -qlevel set level of message suppression. The default is 1.

       -sfscale scale input by fscale, the default is 72.

       -y invert y coordinate in output.

       -V (version) prints version information and exits.

       -? prints the usage and exits.

       A complete description of the available	command-line  options  can  be
       found at http://www.graphviz.org/content/command-line-invocation.

EXAMPLES
       digraph test123 {
	       a -> b -> c;
	       a -> {x y};
	       b [shape=box];
	       c [label="hello\nworld",color=blue,fontsize=24,
		    fontname="Palatino-Italic",fontcolor=red,style=filled];
	       a -> z [label="hi", weight=100];
	       x -> z [label="multi-line\nlabel"];
	       edge [style=dashed,color=red];
	       b -> x;
	       {rank=same; b x}
       }

       graph test123 {
	       a -- b -- c;
	       a -- {x y};
	       x -- c [w=10.0];
	       x -- y [w=5.0,len=3];
       }

CAVEATS
       Edge splines can overlap unintentionally.

       Flat  edge  labels  are	slightly broken.  Intercluster edge labels are
       totally broken.

       Because unconstrained optimization is employed, node boxes can possibly
       overlap	or  touch unrelated edges.  All existing spring embedders seem
       to have this limitation.

       Apparently reasonable attempts to pin nodes or adjust edge lengths  and
       weights can cause instability.

AUTHORS
       Stephen C. North 
       Emden R. Gansner 
       John C. Ellson 
       Yifan Hu 

       The   bitmap   driver   (PNG,   GIF   etc)   is	 by   Thomas  Boutell,
       

       The Truetype font renderer is from the Freetype Project (David  Turner,
       Robert	Wilhelm,   and	Werner	Lemberg)  (who	can  be	 contacted  at
       freetype-devel@lists.lrz-muenchen.de).

SEE ALSO
       This man page contains only a small amount of the  information  related
       to  the	Graphviz layout programs. The most complete information can be
       found at http://www.graphviz.org/Documentation.php, especially  in  the
       on-line	reference pages. Most of these documents are also available in
       the doc and doc/info subtrees in the source and binary distributions.

       dotty(1)
       tcldot(n)
       xcolors(1)
       libgraph(3)

       E. R. Gansner, S. C. North,  K.	P.  Vo,	 "DAG  -  A  Program  to  Draw
       Directed	 Graphs",  Software - Practice and Experience 17(1), 1988, pp.
       1047-1062.
       E. R. Gansner, E. Koutsofios, S. C. North,  K. P. Vo, "A Technique  for
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				 12 July 2013				DOT(1)