This function allows you to layout the display of network elements in the topology map.
Circle Selected Nodes: When selected, the cursor becomes a crosshair. You should click once on the map to pick the center of a circle, and click a second time to choose the radius of the circle. All the points that are currently selected (highlighted) are moved onto the circumference of the circle at equally spaced intervals.
Distribute Selected Points: When selected, the cursor becomes a crosshair. You should click once on the map to pick the center of a circle, and click a second time to choose the radius of the circle. All the points that are currently selected (highlighted) are laid out on the map in a way that's easier to see. They are fitted inside the circle that you chose. If any of the points are collapsed groups, the groups are expanded, will have their contents distributed, and are collapsed again, and so on recursively.
Distribute Selected Points Within Groups: This option is available in the Layout menu only after selecting collapsed groups. For each selected group, the points are distributed for that group, and if multiple groups are selected, they are distributed in a way such that there is little overlap between the groups when they are expanded.
Straighten Selected Nodes: This feature is like Circle Nodes, but puts the selected points onto a horizontal line, equally spaced. (Rotate it with the Drag/Rotate tool to align the selected points vertically instead of horizontally.)
Flip: This feature flips the entire layout vertically or horizontally depending on your selection.
Stiffen: When there are multiple links between two nodes but some of the links are hidden from view, the parallel links may be spread apart too wide or unevenly or all to one side. In this case, selecting Stiffen Visible Curves will bring the parallel links closer together and center them. Select Unstiffen All to undo this stiffening. Option is only relevant when Draw Multiple Links as Curves is turned on in the Map Preferences.
Reset by Lat/Lon: Selecting this option will reset the network topology to its original geographical layout (provided that the LAT/LON coordinates are used in the network). This function is useful when you want to view the network in its geographical layout according to previously specified Lat/Lon values.
Set Lat/Lon From Map: Selecting this option will assign Lat/Lon values to all selected nodes based on their current location on the Map. This function is useful if you have manually moved nodes on the map to desired locations and wishes to save these locations for future sessions.
Quick Layout: Recomputes the X, Y coordinates of all the points using the program's algorithms to try to lay them out clearly. This is the same algorithm used when a Topology View is opened and no saved coordinates are available. If latitude/longitude coordinates are available, they are used to position the nodes, and nodes with the same Lat/Lon are laid out at the city’s location in a small radius around the city center. The full recalculation could take a long time for large networks.
Detail Layout: This topology layout algorithm attempts to distribute the nodes and links as a planar graph. Meaning the topology is drawn in such a way that links intersect only at nodes, or no links cross each other. This layout is useful to create a topology to display a minimal amount of links crossing over each other while keeping node groups together. Various parameters relating to the geographical Lat/Lon position, distance proximity to other nodes, link length, and groups can have their cost weights adjusted. Adjusting these weights will impact the algorithm’s topology display.
Grid Layout: This topology layout algorithm lays out nodes on a grid. The “Intersect Weight” field can be used to reduce line crossing-- the higher the value, the lower the number of line crossings. If you would like to rerun the calculation from the previous iteration’s layout, select the Continue from previous layout if possible checkbox. For Layout, Geographical Group places the groups at the mean lat/long position of the nodes within the group and rearranges the nodes within in a radius determined by the distance to the nearest neighbor. Abstract Group treats the network hierarchically and lays the groups out in a grid as "nodes" - then lays the nodes within the groups out within a radius determined by the distance to the nearest neighbor. "Abstract” will calculate the layout ignoring any group information. “Geographic Group” and “Abstract Group” will consider group information. Search Breadth: With a narrow search breadth, changes that make the solution worse are more likely to be rejected. At the end of the iterations, only changes that make the answer better are accepted. However, at the beginning, you can go backwards -- the probabilities of accepting an answer change as the iteration progresses. For the Iterations, specify the number of iterations to run for the optimization problem, for example, 500.