Introduction
This Step represents the arrival point of the application, i.e. the graphical
representation of the learned network. On top of the window containing the graph
there is a Menu bar by which it is possible to personalize the aspect of the graph: the
submenu commands (explained in the following pages) allow a better visualization
and comprehension of the information contained in the graph.
Menu File
With this menu it is possible to perform standard operations on the graph:
· Save as...: it allows the user to export the graph as an image file (the supported
formats are Jpeg, PNG, and Bitmap, in increasing order of image quality) in
order to be able to print it or include it in reports, presentations etc...;
· Close: it closes the graph window without saving it.
Menu Graph
This menu contains the commands that influence the graph structure:
· Remove isolated nodes: through this command it is possible to eliminate from
the graph all nodes that have no parents and no children, in order to better
visualize the connected portion of the network. By removing this control, all
isolated nodes are re-visualized in the graph.
· Layout: this is a submenu that allows modifying the layout, i.e. how the nodes
are placed within the graph area. There are three possible choices:
1. Circle Layout: all nodes are placed in a circle. This is a very simple
layout that is good for small-medium networks, while it is not very
useful for large networks.
2. KK Layout: based on the Kamada-Kawaii algorithm, this layout
considers the nodes as stiff rings and the links between them as
springs. The idea is to try to minimize the system energy by deriving
the equations that link nodes. This algorithm allows a good
visualization of networks of any dimension.
3. ISOM Layout: it is based on the Self-Organizing Maps algorithm. This layout considers the graphic area as a topographic map on which nodes have to visualized. A uniform prior distribution identifies the possible node positions, while the algorithm places nodes linked by relationships in close points.
Menu Visualization
The menu includes commands that modify the size and colors of the graph:
· Zoom: executing this command. a window with controls to zoom in and out of
the graph will appear;
· Color: this submenu allows modifying all graph colors:
1. Nodes borderline color: it indicates color of node borders;
2. Nodes fill color: it indicates the filling color for nodes;
3. Arcs color: it is the color of arcs connecting nodes;
4. Background color: it is the color of graph background.
Menu Help
From this Menu it is possible to have help for the current screen:
· Help!: it opens this guide at the page referring to the current step;
· Tutorial: it visualizes a step-by-step guide to the use of the toolbox;
· About: it visualizes the credits for the toolbox.
