I have basic program using rgl library which creates dot file and
display it using dotty.

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require 'rgl/adjacency'
require 'rgl/dot'
dg = RGL::DirectedAdjacencyGraph[1,2 ,2,3 ,2,4, 4,5, 6,4, 1,6]
dg.dotty
*************************************************

I have modified this program to change default property as follows:

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require 'rgl/adjacency'
require 'rgl/dot'
dg = RGL::DirectedAdjacencyGraph[1,2 ,2,3 ,2,4, 4,5, 6,4,
1,6].to_dot_graph("fontsize"=>30)
*************************************************


I have following questions:
1. How can I save/view this as dot file?
2. How can I apply property to vertices and edges
3. Is there any way I can add my own property key/value to vertices and
edges

Any small program will be wonderful help to ruby community who wants to
use this wonderful library.