L. A. Rowe, M. Davis, E. Messinger, C. Meyer, C. Spirakis, and A. Tuan, `A browser for directed graphs', Software--Practice and Experience, 17(1), 61--76 (1987).  Home/Search   Document Not in Database   Summary   Related Articles   Check

....to be, the view might still be far too cluttered with information. A Browser for Directed Graphs 1987 This method concentrates on the graph layout issue. It was determined that graph layout should not be called automatically but only when one or more of the following conditions are met [ROWE87]: The user explicitly requests a new layout. A particular subgraph becomes too complicated. The subgraph partition must be changed. Either a set of nodes are to be moved or a subgraph is to be partitioned. If the criteria for deciding when a graph has become too complicated varies for ....

Rowe, L., Davis, M., Messinger, E., Meyer, C., Spirakis, C., and Tuan, A. "A Browser for Directed Graphs," Software--Practice and Experience, 17:1, January 1987, 61--76.

....of composing a multimedia message which consists of a textual data, one annotated image, one graphics, and two video clips. For the hypergraph structure, currently a degenerated version of a tree like structure has been implemented. It is based on the algorithm of a graph browser, called GRAB [9]. The forthcoming version will provide a generalized hypergraph structure for messages with associated timeline so that message readers can easily recognize the time relation among SMOs in one message which may be related to several previous messages. Figure 5 shows two windows: 1) a display ....

L. Rowe, M. Davis, E. Messinger, C. Meyer, C. Spirakis, and A. Tuan, "A Browser for Directed Graphs", Software - Practice and Experience, Vol. 17(1), January 1987, pp. 62-76.

....is partitioned into k layers. Indeed, the drawing of a k layered network can be carried out by dividing the network into k 1 2 layered subnetworks and by applying the heuristic presented in [17] Several heuristics have been proposed for edge crossing minimization in bipartite graphs (see [19, 3, 17, 5, 7, 20]) A common characteristic of these approaches is to consider one vertex at a time, and to compute its position in the layer independently from the other vertices. The median heuristic [7] is the only one for which an upper bound on the error is known, i.e. the number of crossings computed is at ....

L.A.Rowe, M.Davis, E.Messinger, C.Meyer, C.Spirakis, A.Tuan, "A Browser for Directed Graphs", Software Practice and Experience 17, 1, 61-67, 1987.

....passes that have a factor of O(V) in their running time. The second pass orders nodes from left to right within ranks. This pass tries to reduce edge crossings (P2) subject to the constraints on node order implied by flat edges (P1) It is based on an iterative technique like that of [S81][R86]. The key improvements are a new weight function and local optimizations. We call the weight function the generalized median ; it produces less crossings by reducing the effects of widely spread nodes, and is inexpensive to compute. Informally, the generalized median of a node with respect to an ....

Rowe, L. A., Michael Davis, Eli Messinger, Carl Meyer, Charles Spirakis, and Allen Tuan. "A Browser for Directed Graphs," Software: Practice and Experience 17:1, pp. 61-76 (1986).

....digraph into a proper layered network. This can be achieved by placing all nodes with no outgoing edges in layer 0. Each remaining node v is placed in layer L m , where m is the longest path from v to a node in layer 0. This is called the longest path layering and is commonly used (see [3] [4]) To make the layered network proper, invisible dummy nodes are inserted where edges cross several layers. See Fig. 3 1(a) for how a layered network might look like before dummy nodes are inserted and Fig. 3 1(b) for how the same layered network would look like after the dummy nodes are inserted. ....

....problem. A simple depth first search can be used, preferably starting with a node with a low outdegree, reversing edges that would form a cycle during the traversal. This procedure is rather like a topological sort, where backedges are ignored. Several authors have used this technique (see [3] and [4]) L 5 y=5 L 4 y=4 L 3 y=3 L 2 y=2 L 1 y=1 L 5 y=5 L 4 y=4 L 3 y=3 L 2 y=2 L 1 y=1 11 Although the depth first search technique is very simple and fast, it is not very effective. In [6] another heuristics that give fewer upward edges is proposed. The heuristic is based on the intuition that ....

L. Rowe, M. Davis, E. Messinger, C. Meyer, C. Spirakis, and A. Tuan, "A Browser for Directed Graphs", Software Practise and Experience 17 (1) (1987), 61-76.

....ignored, since the rank of a leaf is trivially determined in an optimal ranking. 2.1 Making the graph acyclic A graph must be acyclic to have a consistent rank assignment. Because the input graph may contain cycles, a preprocessing step detects cycles and breaks them by reversing certain edges [RDM]. Of course these edges are only reversed internally; arrowheads in the drawing show the original direction. A useful procedure for breaking cycles is based on depth first search. Edges are searched in the natural order of the graph input, starting from some source or sink nodes if any exist. ....

Rowe, L. A., M. Davis, E. Messinger, C. Meyer, C. Spirakis, and A. Tuan, "A Browser for Directed Graphs," Software - Practice and Experience 17(1), January, 1987, pp. 61-76.

....creating a new instance of one of the schema entities may be achieved by selecting the corresponding icon. By a similar method, queries can also be performed over the schema. Navigational queries can be accomplished by browsing the schema graph. A general purpose browser for graphs is described in [Rowe87]. Techniques for graph browsing such the use of fish eye views [Sarkar92] can also be used. A graph based UI for database ad hoc queries is described in [Doan93] The schema graph is displayed in a window. The schema window also allows the user to select the nodes which are relevant to the query. ....

Rowe, Lawrence A., Davis, Michael, Messinger, Eli, Meyer, Carl, Spirakis, Charles, and Tuan, Allen, "A Browser for Directed Graphs", Software - Prectice and Experience, vol. 17(1), 61-76, January 1987. 29

....specific software visualization principles can be applied. 2.3.1. Design for Aspect Aspect describes which aspect of the software is to be visualized [MYE90] data visualization Systems range from static displays, for instance Incense [MYE83] a system for displaying data structures) GRAB [ROW87] (a system for browsing trees) the interactive graph layout program described in [HEN91] to dynamic data visualization such as VIPS [SHI91] which displays linked lists) PV Prototype [BRO85a] and GMB [JAB89] program visualization Program visualization can range from static views such as ....

Rowe, L.A., Davis, M., Messinger, E., Meyer, C., Spirakis, C., and Tuan, A. (1987). "A Browser for Directed Graphs."Software - Practice and Experience, 17(1), pages 61-76.

....Algebra Specific Circle vertex Symmetric Linear Progr. Bipartite Constrained Uniform density Heuristic Orthogonal Minimum edge length Non overlapping vertices Table 1: Some characteristics of graph drawing algorithms. Algorithms for drawing directed graphs and DAGs can be found in [8] 7] and [15]. Most of these algorithms draw general directed graphs by initial cycle breaking by edge reversion and a subsequent DAG algorithm. The DAG algorithms from Bell Labs, described in [8] and [7] use a more complicated multi pass algorithm which combines depth first search, linear programming and ....

....is an adaptation of Fruchterman and Reingold s simulatedannealing based algorithm from [6] Vertices are set to repel each other, while edges attract adjacent vertices. The graph is then embedded using an iterative process. Hierarchical This is an adaptation of the directed graph methods in [15] and [4] Cycles are broken by edge reversal, vertices are assigned to levels by their topological ordering, and the resulting hierarchy is iteratively combed to minimize edge crossings. This combing is done by repeated reordering of levels using vertex barycenters. Barycentric This is a ....

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L. A. Rowe, M. Davis, E. Messinger, C. Meyer, C. Spirakis, and A. Tuan. A browser for directed graphs. Softw. -- Pract. Exp., 17(1):61--76, 1987.

.... This is due in part to the inability to specify the aesthetic criteria individuals use in understanding graphs[22] Nonetheless, for certain restricted classes of graphs in which graph theoretic expressions of aesthetic criteria can be specified, satisfactory algorithms have been developed[8, 46, 58]. Some of the aesthetics for drawings of general undirected graphs are symmetry, minimization of edge crossings and bends in edges, uniform edge lengths, and uniform node distribution. These aesthetics are such that optimality of one may prevent optimality in others. Additionally, graph layout ....

Rowe, L. A., Davis, M., Messinger, E., Meyer, C., Spirakis, C., and Tuan, A. (1987.) "A browser for directed graphs". Software Practice and Experience, 17(1), 61-76.

....daVinci. The primary aim was to create a universal system that could be used by arbitrary applications as a user interface to display directed graphs in many different visualization styles. There are a lot of powerful graph visualization tools such as CG [3] the prototype of Henry [4] GRAB [5], GraphEd [6] GMB [7] dot [8] etc. A detailed survey of each approach would exceed the size of this article. Unfortunately, most of the existing systems for graph Technical Report No. 5 94 Department of Computer Science University of Bremen 2 The Graph Visualization System daVinci A ....

....the scale for getting an overview. Improving the graph layout manually (fine tuning) Experiences have shown us that users often like to influence or modify an automatically generated layout in details, because standard representations are rarely perfect. Some graph drawing systems such as GMB [5], dot [8] or EDGE [9] provide constraints for controlling the graph layout in a declarative way. For example, to define the order of several nodes in the visualization, one has to formulate the desired effect in the constraint language and to add these constraints to the input graph. This method ....

[Article contains additional citation context not shown here]

L. A. Rowe, M. Davis, E. Messinger, C. Meyer, C. Spirakis, A. Tuan (1987) A Browser for Directed Graphs. Software - Practice and Experience, Vol. 17, No. 1, pp. 61-76.

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L. A. Rowe, M. Davis, E. Messinger, C. Meyer, C. Spirakis, and A. Tuan, `A browser for directed graphs', Software--Practice and Experience, 17(1), 61--76 (1987).

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L. A. Rowe, M. Davis, E. Messinger, C. Meyer, C. Spirakis and A. Tuan, `A browser for directed graphs', Software---Practice and Experience, 17, 61--76 (1987).

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L. A. Rowe, M. Davis, E. Messinger, C. Meyer, C. Spirakis and A. Tuan, "A browser for directed graphs", Software Practice and Experience 17 (1987) 61-76.

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L. A. Rowe, M. Davis, E. Messinger, C. Meyer, C., Spirakis and A. Tuan. "A Browser for Directed Graphs" , Software Practice & Experience, Volume 17, #1, pp. 61-76, January 1987.

No context found.

L. A. Rowe, M. Davis, E. Messinger, C. Meyer, C., Spirakis and A. Tuan. "A Browser for Directed Graphs" , Software Practice & Experience, Volume 17, #1, pp. 61-76, January 1987.

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pp. 61-76

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Rowe, L. A., Davis, M., Messinger, E., Meyer, C., Spirakis, C., and Tuan, A., "A Browser for Directed Graphs," Software-Practice and Experience 17(1), pp. 61-76 (January 1987).

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