Visual Analysis on the WEB: Animating High Density Multidimensional Data

SAS® can be used as a powerful tool for systematically exploring, animating, and sharing animated multidimensional data structures using goptions dev=gifanim statement in SAS/GRAPH®. Three different examples of data animation and visual analysis are provided in this paper (viewable at http://idt.net/~haftan by selecting research). The first, and perhaps easiest example, demonstrates the visual analysis of spatial data revealing the 3-dimensional functional neuroanatomical structures of the rat brain reconstructed from hundreds of digitized 2-dimensional scans. These reconstructed brains are then viewable from moving external as well as internal perspectives revealing previously obscured surfaces and relationships. The second example presents a greater challenge to the analyst through 3-dimensional and 4-dimensional animations of a high-density temporal data comparing electrophysiologic responses to different stimuli from several hundred milliseconds of real time electrode recordings at 128 sites on the human scalp. The last and most difficult example animates a-temporal, a-spatial data demonstrating "gap analysis" as a method for understanding and predicting the behavior and location of prime numbers. In each example, algorithms are developed to create dimensions and objects from raw data that maximize the researchers' ability to access, summarize, explore, question, and share large multidimensional data structures. Unlike many other software systems, SAS provides a fast and simple way to produce WEB "browse-able" movie formats that do not require viewers to have a copy of SAS.