Visualizing operations on temporal data

An interactive data browsing environment designed specifically to support temporal manipulations is described. A formal system of temporal operations is combined with a visual system for interactive temporal data display. The basic temporal construct is a time line. For each of the basic time-line operations, the effects of each operator, including exceptions and boundary conditions, are defined. For each formal definition, a precise visual analog of the operation is given. A time-line browser, an editor for time lines, which implements this formalism is described and applied to biomedical data (e.g. diabetes patient data)