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- Use the Windows Start menu to launch Gvedit, which is part of Graphviz; and
- Choose File » Open and select the .DOT file of interest. Gvedit will respond by opening a two windows. One window will contain the textual representation of the arc-node network as shown in the central window in Figure 7; and Click the Run button on the Gvedit toolbar (Figure 7)
- and on will contain the visual representation as shown in Figure 7.
Figure 7. Gvedit (opening an arc-node network)
Graphviz always generates a graphical representation of your arc-node network in two forms. One is displayed on your screen and the other is saved as a file. 
GVEdit will attempt to save to a .png file initially, but the file name must be configured via the Settings button shown in Figure 7. This will open the dialog shown in Figure 8. By default, the version saved as a file is in .GIF png format but you can change this using the Output File Type popthe Output File Type pop-up menu in Figure 8. Note that Graphviz can also generate high-resolution vector-based representations such as .SVGsvg.
By default, the file is saved in the same folder as the original .DOT file. You can change this by clicking the ellipsis button (...) to the right of the Output File Name field in Figure 8.
Figure 8. Graphviz settings dialog
Once the settings have been configured to your requirements, click OK. click OK in the settings dialog. Then click on the Layout button in the main menushown in Figure 7.
Figure 9 is an excerpt from an arc-node network diagram produced by Graphviz. The elements inside the blue rectangle correspond with a Splitter node in the original Source schematic.
Figure 9. NetLP arc-node network for Splitter node
