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Operation Toolpad > Geometry Command Button > Edge Vertex Command Button > Create Edge Vertex
Create the vertices by entering the coordinates under Global and the label under Label:
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Operation Toolpad > Geometry Command Button > Vertex Edge Command Button > Create Vertex Edge
Create the edge 4-12 by selecting the vertex 1 followed by vertex 2. Click Apply. GAMBIT will create the edge. You will see a message saying something like "Created edge: edge.1'' in the Transcript window.
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Operation Toolpad > Geometry Command Button > Edge Command Button > Create Edge > Arc
Right click on the Create Edge to see more options. Select the Arc icon. (The default option is Straight)
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