Last modified 8 years ago Last modified on 08/23/10 14:07:01

VIQUEN: A Visual Query Engine for RDF

Tutorial 1: Extracting information from the Foundational Model of Anatomy (FMA)

Part 3: Visualizing the query results

In the first part of this tutorial, you worked through constructing a simple query which extracts information from the Foundational Model of Anatomy (FMA) ontology. In part 2, you executed the query. In this part, you will visualize and explore the query results.

(Click here for Part 1: Formulating the query)
(Click here for Part 2: Executing the query)

To return to the main VIQUEN documentation page, click here.

Step 1 - Opening the visualization environment

From completing parts 1 and 2 of this tutorial, you should have the visualization environment open with the following display.

In the main visualization workspace we can see the "Brain" node, which we know is the root of our extracted tree, and the first layer of "regional parts" of this node: "forebrain", "midbrain" and "hindbrain".

Step 2 - Navigating the tree view

On the left-hand side of the screen you can see the "Node tree" option.

Click on the "Brain" label in the node tree. You will see that the "Brain" node in the main visualization workspace is automatically selected.
Expand the "Brain" node in the node tree by clicking on the triangle to the left of the "Brain" node. Expanding different parts of the node tree provides one way to explore the tree of query results.
Expand a few layers of the results in the node tree, and then click on any node. You will see that the node clicked on is made visible in the main visualization workspace (with its child and parent nodes).

Step 3 - Navigating the list view

To the immediate right of the node tree, you can see the "Node list" option. Click on this. You will see an alphabetized list of all the nodes in the query results (note that not all of the nodes are currently displayed in the main visualization workspace).

Click on the "Brain" label in the node list. You will see that the "Brain" node is once again selected and made visible in the main visualization workspace. Selecting nodes in the "Node list" provides another way to navigate the query results.

Step 4 - Getting information from a node

You should have the "Brain" node visible in the main visualization workspace. Hold the mouse over the node's information icon . You will see a box pop up showing the name of this node, and the number of incoming and outgoing edges that the node has.
Try the same thing for the other nodes in the workspace.

Step 5 - Easy navigation through child nodes

Find the "Hindbrain" node (it is a child of the root "Brain" node). Click on the "Hindbrain" node's "show children" button . You will see the child nodes of "Hindbrain" are added to the visualization workspace. Click on the "show children" button of the "Medulla oblongata" node. Once again, the child nodes will be added to the visualization.
Note that if a node has no children, it does not have a "show children" button.

Step 6 - Exploring layouts

We will now explore some alternative layout options for the visualization. Click on the "Diagram" tab located at the top of the screen.
Choose Diagram -> Layout -> Vertical Hierarchical.
This will change the current layout of the visualization to be vertical and hierarchical.

Feel free to explore the other layout options, and when you're done go back to the "Horizontal hierarchical" layout.

Step 7 - Other exploration options

If you have not done so, switch back to the original "Horizontal hierarchical" layout.
Click on the "forebrain" node (a child node of the "Brain" root node).
Right click on this node and you will see the visualization pop-up menu.
Navigate to the "Show/Hide?" menu, and select "Show children". This will show the children of the "forebrain" node.
Try the same thing but this time select "Hide children". You will now see that the children of "forebrain" are hidden.
Spend some time playing around with the other "Show/Hide?" options. Also explore the "Select" submenu, used for selecting different parts of the graph.

Step 8 - Navigating the workspace outline

Right-click in the main visualization menu, and from the "Show/Hide?" pop-up submenu, select "Show All".
Find the workspace outline at the bottom left-hand side of the screen.

The dark blue rectangle indicates the portion of the workspace that is currently displayed.
Click and drag this rectangle in the workspace outline. You will see that the visible part of the workspace is automatically changed.

Step 9 - Saving and loading visualizations

To save the visualization, click on the save button . Select an appropriate directory location and filename, like "Brain visualization", and click "Save".
This visualization can be now be loaded using the open button .
If you wish to load an XML/RDF file rather than a saved visualization, you may do this using the load RDF button .

Congratulations - you're done

In completing this tutorial you have successfully

  1. Formulated a query to extract information from the FMA ontology.
  2. Executed the query.
  3. Visualized and explored the query results.

Try another tutorial:
Tutorial:Binding variables
Tutorial:Combining operations

To return to the main VIQUEN documentation page, click here.