Arranging nodes to make clear diagrams

Analytica User GuideCreating Lucid Influence DiagramsArranging nodes to make clear diagrams

Adjust node size: If you have nodes of different sizes, you can make them more consistent by selecting Adjust size (Ctrl+T) from the Diagram menu.

Adjust size examines the node’s contents (its title and picture), font, where word wraps would occur, the the default minimum node size (as set on the Diagram Style... dialog), the current height and width, the edge alignments of others nodes also selected, containment relationships of nodes that grouped within text or picture nodes, locations of corners and edges relative to the grid (when Snap to grid is on), and aspect ratios, and makes tradeoffs between these considerations to select a good size for the selected node(s). When you select Adjust size several times in succession (or by press Ctrl+T multiple times), it cycles through different tradeoffs options, so if you don’t like the sizes selected at first, just press Ctrl+T several more times until you see an arrangement of node sizes that works well.

It often works good to select many nodes simultaneously, especially if your diagram contains inputs fields with left or right alignments, or fields that are grouped within text or picture nodes. With multiple nodes selected, Adjust size generally attempts to preserve containment and align- ment relationships.

Adjust size uses utilizes these various criteria, and avoids silly word wrap boundaries, only when the diagram uses ClearType fonts. This is the case for all models created in Analytica 4.4 or later.

If you load a model created in Analytica 4.3 or earlier, you will need to enable ClearType fonts by selecting Set Diagram Style... on the Diagram menu with the top-level model diagram in focus. The ClearType fonts checkbox appears on that dialog only when you are editing a legacy model. When you turn ClearType fonts on for the first time, the font width and spacing changes slightly, which usually causes some nodes to word wrap in new, undesireable places. A good trick at that point is to select all nodes by pressing Ctrl+A, then select Adjust size repeatedly until a satisfactory appearance is reached.

You can also resize several nodes by the same amount simultaneously by following these steps:

1. Select the nodes to resize.
2. Resize one of the selected nodes by dragging one of its handles. All other selected nodes are also resized.

Selected nodes can also be set to be the same width, height, or size. To set the size of selected nodes to be the same size use the Make Same Size submenu in the Diagram menu. The last node selected will be the only node with solid selection handles and is called the reference node. The options are:

• Make Same Size Width — Sets all the selected nodes to the width of the reference node.
• Make Same Size Height — Sets all the selected nodes to the height of the reference node.
• Make Same Size Both — Sets all the selected nodes to the width and height of the reference node.

Align to the grid: It usually looks best when the centers of the nodes are aligned along a common horizontal or vertical line, so that many arrows are exactly horizontal or vertical. The square grid of 9x9 pixel blocks underlying each diagram makes this easy. When the grid is on (the default), each node that you create or move is centered on a grid intersection. This default makes it easier for you to position nodes so that arrows are exactly horizontal or vertical when nodes are aligned vertically or horizontally.

To turn the grid off in edit mode, uncheck Snap to Grid from the Diagram menu. When the grid is off in edit mode, the grid is still visible, and you can move the nodes pixel by pixel.

If nodes are not centered on a grid point, re-center them by following these steps:

1. Select all nodes in the diagram with the Select All (Control+a) command from the Edit menu.
2. Select Align Selection To Grid from the Diagram menu (Control+j).

Align selected nodes: To line up selected nodes with each other, use the Align submenu in the Diagram menu. You can align selected nodes in the following ways:

• Align the left edges.
• Align the centers left and right — this aligns the centers horizontally.
• Align the right edges.
• Align the left and right edges — this makes all the selected nodes the same width and aligns them so that their left and right edges match up.

• Align the top edges.
• Align the centers up and down — this aligns the nodes so that their centers are at the same vertical height.
• Align the bottom edges.

Distributing nodes: To distribute selected nodes evenly, use the Space Evenly submenu in the Diagram menu. You can distribute selected nodes so that the centers are evenly spaced vertically (Space Evenly → Across) or horizontally (Space Evenly → Down). To ensure that the nodes end up on the grid, use Space Evenly → Across, on grid and Space Evenly → Down, on grid. The “on grid” variations may change the begin-to-end span of the nodes, while the non-on-grid variants pre- serve the span but may place nodes off grid.

Choosing which node is in front: By default, text and picture nodes are behind arrows, and arrows are behind all other types of nodes (decision, chance, variable, etc.). If nodes overlap, the more recently created node is on top of the older node. You can change this order by selecting a node(s) and using the Send to Back and Bring to Front options from the right-click menu.

Hide less important arrows: Sometimes so many nodes are interrelated that it is hard or impossible to arrange a diagram to avoid arrows crossing each other or crossing nodes. It might be helpful to hide some arrows that show less important linkages. For example, indexes and functions are often connected to many other variables; that’s why arrows to and from them are switched off by default.

You can hide all of the arrows linking indexes, functions, or modules, or the grayed feedback arrows in dynamic models, using the Set Diagram Style command from the Diagram menu in the Diagram Style dialog. You can also hide the input or output arrows from each node individually, using the Set Node Style command in the Node Style dialog.

Keep diagrams compact: Screen space is valuable. To save space, keep nodes close together, leaving enough space between them for the arrows to be visible.

When first creating a diagram, use plenty of space. Your diagram window can be as large as your monitor screen. Using this space, first find a clear arrangement, which minimizes arrow crossing and avoids node overlaps. Then, you can usually make the diagram more compact by moving the nodes closer together and moving the entire diagram closer to the upper-left corner of the win- dow. Finally, you can reduce the window size to fit the diagram.

See Also

• Diagram window
• Diagram Style dialog
• Node Style dialog
• Node Alignment, Sizing, and Spacing

Guidelines for creating lucid modelsArranging nodes to make clear diagramsOrganizing a module hierarchy