graphviz dot language

install

1. on mac

        brew install graphviz
   

language

1. subgraphs and clusters

   1. roles in graphviz

       # first role
      
       A -> {B C}
      
       # is equivalent to
       A -> B
       A -> C
      
       # 2 second role
      
       subgraph {
           rank = same; A; B; C;
       }
      

   2. lexical and semantic notes

       # a graph must be `digraph` or `graph`
       strict graph {
           a -- b
           a -- b
           b -- a [color=blue]
       }
      

2. output formats

3. node edge and graph attributes

   1. all graphviz attrs are specified by name-value pairs

       abc [fillcolor=red]
      
       abc -> def [arrowhead=diamond]
      
       # `color`
       digraph G {
           a -> b [dir=both color="red:blue"]
           c -> d [dir=none color="green:red;0.25:blue"]
       }
      
       # `constraint`
       digraph G {
           a -> c;
           a -> b;
           b -> c [constraint=false]
       }
      

   2. attribute type description

       arrowType
       normal
       inv
       dot
       invdot
       odot
       invodot
       none
       tee
       empty
       invempty
       diamond
       odiamond
       ediamond
       crow
       box
       obox
       open
       halfopen
       vee
       circle
      
       # dirType
       forward
       back
       both
       none
      
       # basic style settings for nodes
       solid *
       dashed
       dotted
       bold
       rounded
       diagonals
       filled
       striped
       wedged
      
       # basic style settings for edges
       solid *
       dashed
       dotted
       bold
      
       # basic style settings for clusters
       solid
       dashed
       dotted
       bold
       rounded
       filled
       striped
      

4. node shapes

   1. polygon-based

       box
       polygon
       ellipse
       oval
       circle
       point
       egg
       triangle
       ...
      
       digraph G {
           {
               node [margin=0 fontcolor=blue fontsize=32 width=0.5 shape=circle style=filled]
               b [fillcolor=yellow fixedsize=true label="a very long label"]
               d [fixedsize=shape label="an even longer label"]
           }
           a -> {c d}
           b -> {c d}
       }
      

   2. record-based

   3. user-defined

5. colors