D3 layer visualization

The layer module uses the D3 partition layout to visualize the tree like layer structure in Wandora. It uses the open source JavaScript visualization library D3.js. The service module's alias in Wandora is layer and the URL of the visualization is

http://127.0.0.1:8898/layer

By default the layer visualization pulls 5 child layers per parent layer and 500 topics per layer. These limits may be overridden with the nl and nt URL query parameters respecively. An usage example of the visualization is provided below.

Note that as with D3 the browser support of D3 visualizations in Wandora is limited to IE9+ and up to date versions of Firefox, Chrome (+Chromium), Safari and Opera.

First layers are created and populated in Wandora. In this case data is extracted with the Freebase extractor and New York Times Article Extractor about Linus Torvalds and Richard Stallman.

The visualization now shows both the layer structure and topics in a circular partition layout as well as bezier curves between topics from different layers to visualize topics merging with each other. A 0.37 ratio of merged topics per all topics is shown along with other statistics.

Topics can be selected with a text filter. Here topics matching "GNU", "Linux" and "Open" are shown both in the visualization and the "Now selected" table. Mousing over either the group of merged topics in the visualization or the table highlights the topics in both. Topics can also be selected and deselected by clicking on them in the visualization.