Abstract: A node-link structure is laid out in a space with negative curvature, such as the hyperbolic plane. Nearby relationship data are obtained for an element in the structure, indicating information about nearby node-link relationships; then layout data for the element are obtained, based on the nearby relationship data. The layout data indicate the element's position relative to a parent in the negatively curved space. The layout data can indicate a position displacement and an angle displacement between the parent and the element. The nearby relationship data can be obtained by counting grandchildren of the parent for each child of the parent that is in a set that are being or have been laid out. The counts can be used to obtain a radius and an angle for each child in the set, and the radii and angles can be used to obtain the position displacement and angle displacement. The nearby node-link relationships can thus include only relationships among the parent and its children and grandchildren.

Abstract: In a series of iterations, each of which automatically traverses a set of elements of a node-link structure, an iteration modifies the part of node-link data defining the structure that is in memory. The modified part of node-link data is more likely to define the set of elements that will be traversed by the next iteration. The iteration can determine whether to remove any of the part of node-link data, and then apply a criterion, such as a navigation history criterion or a least recently traversed criterion, to determine which of the part to remove. The iteration can also determine whether its set of elements includes an element with children that are not defined by the part of node-link data in memory, and can obtain a modified part that defines those children. Each iteration can, for example, prepare and present a representation of the node-link structure.

Abstract: A software visualization tool consistent with the present invention integrates OLAP functionality with focus+context based techniques for navigation through and inspection of large multidimensional datasets. Focus+context based navigation techniques are used to increase the clarity and information content provided to the user. The visualization tool supports a number of operations of the data set, including: select-slice, aggregation, promote/demote, repeat-variables, and sort.

Abstract: A node-link structure is laid out in a space with negative curvature, such as the hyperbolic plane. Nearby relationship data are obtained for an element in the structure, indicating information about nearby node-link relationships; then layout data for the element are obtained, based on the nearby relationship data. The layout data indicate the element's position relative to a parent in the negatively curved space. The layout data can indicate a position displacement and an angle displacement between the parent and the element. The nearby relationship data can be obtained by counting grandchildren of the parent for each child of the parent that is in a set that are being or have been laid out. The counts can be used to obtain a radius and an angle for each child in the set, and the radii and angles can be used to obtain the position displacement and angle displacement. The nearby node-link relationships can thus include only relationships among the parent and its children and grandchildren.

Abstract: A multi-level focus software visualization tool uses a focus+context visualization technique for displaying tables in which multiple table cells may be mapped to a single pixel or a single pixel row. Three or more focus levels may be used instead of the conventional two-focus levels. Accordingly, the whole table presented can be seen on the screen, thus minimizing the mechanical overhead of user navigation and allowing the user to quickly spot trends and outlining data.

Abstract: A sequence of steps presents node-link representations on a display. The sequence includes a first step, a last step, and at least one intermediate step. The first step presents a first representation that represents a first node-link structure. The last step presents a last representation that represents a second node-link structure that is a modified version of the first node-link structure. Both node-link structures include a set of shared elements that include a moving element. The moving element is represented by features that have different positions in the first and last representations. Each intermediate step presents an intermediate representation that includes features representing a subset of the shared elements including the moving element, and each element in the subset is also represented by features in the first and last representations. The feature representing the moving element has object constancy through the sequence of steps.

Abstract: A sequence of steps presents node-link representations on a display. The sequence includes a first step, a last step, and at least one intermediate step. The first step presents a first representation that represents a first node-link structure. The last step presents a last representation that represents a second node-link structure that is a modified version of the first node-link structure. Both node-link structures include a set of shared elements that include a moving element. The moving element is represented by features that have different positions in the first and last representations. Each intermediate step presents an intermediate representation that includes features representing a subset of the shared elements including the moving element, and each element in the subset is also represented by features in the first and last representations. The feature representing the moving element has object constancy through the sequence of steps.

Abstract: In a series of iterations, each of which automatically traverses a set of elements of a node-link structure, an iteration modifies the part of node-link data defining the structure that is in memory. The modified part of node-link data is more likely to define the set of elements that will be traversed by the next iteration. The iteration can determine whether to remove any of the part of node-link data, and then apply a criterion, such as a navigation history criterion or a least recently traversed criterion, to determine which of the part to remove. The iteration can also determine whether its set of elements includes an element with children that are not defined by the part of node-link data in memory, and can obtain a modified part that defines those children. Each iteration can, for example, prepare and present a representation of the node-link structure.

Abstract: A method for recognizing user specified pen-based gestures uses Hidden Markov Models. A gesture recognizer is implemented which includes a fast pruning procedure. In addition, an incremental training method is utilized.

Abstract: A node-link structure laid out in a space with negative curvature, such as the hyperbolic plane, is mapped to a rendering space, such as the unit disk, beginning from a starting element that has both a parent and a child. Data identifying the starting element are obtained, such as based on user signals. The starting element can be located at a starting position in the unit disk. Then a set of other elements can be mapped, each reachable from the starting element by a path that leads only through elements in the set. Each element's position in the negatively curved space relative to a preceding element on its path and the position of the preceding element in the rendering space can be used to obtain the element's position in the rendering space. The positions in the unit disk can then be used to present a representation of the node-link structure.

Abstract: Node-link data defining a graph also include tree defining data. The node-link data with the tree defining data further define a tree within the graph. The tree defining data indicate a set of elements in the graph that are represented in the tree. Each of a subset of elements in the set is represented more than once in the tree. For at least one element in the subset, the tree defining data indicate which representations of the element have descendants in the tree and which representations have none. The tree defining data can, for example, be expansion flags for links in the graph that are in the set of elements, with each links expansion flag indicating whether the link's to-node is expanded or contracted in the tree. In response to each of a series of expand and contract signals from a user, an iteration can modify the tree defining data and use it to present a representation of the graph with the indicated node expanded or contracted as requested.