Data Constellation
Last updated
Last updated
A Data Constellation is a graph, a collection of things (nodes) that are connected (via links). It can be used to show connections and relationships. This combines a graph viewer with layout tools that allow you to position your graph. However, it does require two input tables, defining nodes and links. Learn about each Data Constellation feature below:
Data: from 2 tables. The Data Constellations graph is defined by two Data Pool tables: one representing nodes, and the other (optional) representing links. A field in the nodes table names the nodes; two fields in the links table give the two sides of the link in terms of the node names. It is possible to have a Data Constellations with no links. From: Chart Toolbar "Configure Data" ().
2D or 3D: rendering style. Draw in 2D or 3D. 3D requires that a field giving the node height be provided. From: Node Height.
Viewpoint: manage your viewpoint on the data. Pan, zoom, and rotate the view to get the viewpoint that you want. This can be done with the zoom bars in 2D, or with buttons in the for 3D. It can also be done via the viewpoint using the mouse, the keyboard, or the zoom bars. In 2D only, the graph may also be rotated by dragging with the Middle Mouse Button (scroll wheel) depressed starting in a corner of the display.
From: , Zoom Bars, , .
Aggregation: combining data rows for nodes. The node table may contain multiple rows with the same key value. These rows are automatically combined together. If you specify a node height field for 3D or a node size field, the values in that field for the same node are summed before they are used. Link table rows are not combined, however: each link table row forms a separate link. From: ; Node and Link Sizes dialog
Colors: color your graph. The nodes in the Data Constellation chart are colored by the node table color; the links are colored by the link table color. Since these are separate tables, the colors on nodes and links can be different.
If the Data Constellation nodes are aggregated (multiple rows with the same key) and the nodes table is colored by a field other than the node name, than the colors will be "stacked"; there is no way to turn off color stacking in a Data Constellation chart.
Color by field: Data Values determine node and link colors Coloring for the node table is set in the usual way by the application toolbars and menus. For the link table, coloring can be set from the Link Color Selection dialog opened from the chart toolbar. From: Analyze ribbon, "Color Field" drop-down; Chart Toolbar "Set Link Line Color" button/"Link Color Selection" dialog.
Nodes: how are nodes drawn? In 3D mode, you can choose basic node shapes from the Chart Toolbar. The styles are: cone, cylinder, cube, and sphere. You can also choose advanced shapes from the "Glyph Shape" property in the Advanced Properties pane: torus, dodecahedron, icosahedron, octahedron, tetrahedron, or disc.
You can scale all nodes (and links) by 30% using the "+" and "-" keys, or with the "Link Scale" and "Node Scale" properties in the . Note that the Link Scale property defaults to 0, so the "+" or "-" keys will have no effect unless a non-zero value is manually set. Node scale should be manually set if the size chosen for nodes is too small to be comfortably seen.
In 3D, nodes may be positioned at their aggregate height, or the links may be drawn on the "floor" to the base of cylinders that extend to the prescribed height. This is set by the "Extrude Glyphs" Advanced Property.
All node shapes can be extruded in 3D, not just the default box shape, but cylinder and cone also work well.
The size and height of a node may be controlled by data from fields in the node table. In 3D, if extruded and both the Height and Size are set, the fields must be the same.
From: Described above.
Links: how are links drawn? The size of links can be controlled by data from a field in the link table. Use Chart Toolbar button "Adjust Node Scale" to open "Node and Link Sizes" dialog.
From: Described above.
Reference Grid: draw grid in 3D? In 3D only, a grid may be included on the background planes for quantitative reference.
From: Advanced Property "Show Grid".
Show Unselected: are Unselected items drawn? Draw or hide glyphs that are totally unselected from this chart only.
Items may only be selected graphically when they are visible.
From: Chart Toolbar "Display Unselected Data" (); Advanced Properties pane "Display Unselected".
Placement: layout your graph as a tree, circle, or strength based. The layout of nodes in your graph is key to making it comprehensible. The Data Constellation Wizard offers a few heuristic algorithms that may be used to determine node placement: Circular, Hexagonal grid, Top-Down Tree, and Angular Tree.
A numeric field from the links table may be used to give the "link weight"; the higher the magnitude of this number, the closer nodes will be placed to each other. Choose this field from the toolbar button "Select the fields for node and link sizing."
Manual positioning is also possible for 2D charts; when the mouse is over a node the pointer turns to a hand; dragging the node with the left mouse button moves its position.
From: As described above.
Directional links: links as arrows. Links may be drawn with arrowheads at the "To" end, in 2D only. The direction of the link is taken from the order the fields were specified in the link table.
From: Advanced Property "Directional Links".
Selection propagation: What happens when you select nodes or links. When you make a selection, you can control how that selection affects attached links (when selecting nodes) or nodes (when selecting links). You can control which can be selected: nodes only, links only, both nodes and links (default), or neither. Separately, you can control how selection is propagated: No linking, Tie Links to Nodes, Tie Nodes to Links (default, means connected nodes are selected when links are), or Tie Both.
Directional links affect selection propagation over links; selection is propagated across a link only in the direction of the link when directional, and to both sides of the link when not directional.
You can also control whether selections made outside of the Data Constellations are propagated between nodes and links. This affects only selections made in other views.
Consider an example, when both nodes and links can be selected and link selection is propagated to nodes. Start by Unselecting everything (i.e., Unselect All in both node and link tables). Sweep just a link; notice that it and any nodes attached to it are selected. Click on just a node to select just that node; notice that the attached links are unaffected.
From: Advanced Properties "Enable Linking", "External Linking", "Selection Linking", "Selection Type".
Labeling: label nodes Nodes can be statically labeled.
Label all selected nodes: Set Advanced Property "Label Selected" to True to cause all nodes to display static labels as long as they are selected.
Label nodes by clicking with the mouse: Set Advanced Property "Mouse Select" to False. In 2D mode, clicking a selected node turns on a static label.
Turn off labels: If any labels have been individually turned on, setting Label Selected to True and then to False causes all node labels to be turned off.
Customizable Focus: what is this item? You focus on a node in the graph by pointing at it for a moment (or force immediate focus by holding down SHIFT or CTRL). By default, the node name is displayed. Multiple focus fields can be shown. If there are additional weighting fields (e.g., node height), that weight is automatically shown as well.
As always, focus is propagated to other views as well if the node represents a single row; if it represents multiple rows, focus cannot be broadcast.
You can customize the focus information for Nodes by changing a format string with the property in the Advanced Chart Properties pane. Clearing this string suppresses focus labeling.
Fonts and title: what fonts are used, how is the chart titled? The font used for labels can be set from the "Chart Titles" dialog (from in the Chart Toolbar) or from the "Label Font" property in the Advanced Chart Properties pane.
The chart may have a title; by default no title is shown. This title may be changed via the "Chart Titles" dialog or the "Title" property, the font may be changed, or the title may be shown or hidden.
From: Chart Toolbar "Edit Chart Titles..."; Advanced Chart Properties "Display Title", "Label Font", "Title", "Title Font".
3D rendering: control 3D rendering.
The range of the X, Y, or Z axis may be set; this controls the aspect ratio of the displayed grid. The default aspect ratio has equal X, Y, and Z axes. Available from the "Adjust Range" button.
Combinations of keyboard and mouse inputs can control 3D viewpoint, scaling, and orientation. See .
From: As described above.
See Also:
