William L. Hibbard

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The VIS-5D system provides highly interactive visual access to 5-dimensional data sets containing up to 50 million data points. The user has easy and intuitive control over animated 3-dimensional depictions of multiple interacting physical variables. VIS-5D is runs on the Stardent ST-1000 and ST-2000 workstations and is available as freeware from the Space(More)
We present a technique for defining graphical depictions for all the data types defined in an algorithm, The ability to display arbitrary combinations of an algorithm's data objects in a common frame of reference, coupled with interactive control of algorithm execution, provides a powerful way to understand algorithm behavior. Type definitions are(More)
Scientists often view computer algorithms as risk-filled black boxes. The barrier between scientists and their computations can be bridged by techniques that make the internal workings of algorithms visible and that allow scientists to experiment with their computations. We describe two interactive systems developed at the University of Wisconsin-Madison(More)
The VIS-AD data model integrates metadata about the precision of values, including missing data indicators and the way that arrays sample continuous functions, with the data objects of a scientific programming language. The data objects of this data model form a lattice, ordered by the precision with which they approximate mathematical objects. We deffme a(More)