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186
An algorithm for drawing general undirected graphs
 Information Processing Letters
, 1989
"... Graphs (networks) are very common data structures which are handled in computers. Diagrams are widely used to represent the graph structures visually in many information systems. In order to automatically draw the diagrams which are, for example, state graphs, dataflow graphs, Petri nets, and entit ..."
Abstract

Cited by 456 (2 self)
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Graphs (networks) are very common data structures which are handled in computers. Diagrams are widely used to represent the graph structures visually in many information systems. In order to automatically draw the diagrams which are, for example, state graphs, dataflow graphs, Petri nets, and entityrelationship diagrams, basic graph drawing algorithms are required.
Graphical Fisheye Views of Graphs
, 1992
"... DEC’s business and technology objectives require a strong research program. The Systems Research Center (SRC) and three other research laboratories are committed to filling that need. SRC began recruiting its first research scientists in l984—their charter, to advance the state of knowledge in all a ..."
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Cited by 218 (3 self)
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DEC’s business and technology objectives require a strong research program. The Systems Research Center (SRC) and three other research laboratories are committed to filling that need. SRC began recruiting its first research scientists in l984—their charter, to advance the state of knowledge in all aspects of computer systems research. Our current work includes exploring highperformance personal computing, distributed computing, programming environments, system modelling techniques, specification technology, and tightlycoupled multiprocessors. Our approach to both hardware and software research is to create and use real systems so that we can investigate their properties fully. Complex systems cannot be evaluated solely in the abstract. Based on this belief, our strategy is to demonstrate the technical and practical feasibility of our ideas by building prototypes and using them as daily tools. The experience we gain is useful in the short term in enabling us to refine our designs, and invaluable in the long term in helping us to advance the state of knowledge about those systems. Most of the major advances
Graphical Fisheye Views
, 1993
"... A fisheye camera lens is a very wide angle lens that magnifies nearby objects while shrinking distant objects. It is a valuable tool for seeing both "local detail" and "global context" simultaneously. This paper describes a system for viewing and browsing graphs using a software analog of a fisheye ..."
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Cited by 169 (0 self)
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A fisheye camera lens is a very wide angle lens that magnifies nearby objects while shrinking distant objects. It is a valuable tool for seeing both "local detail" and "global context" simultaneously. This paper describes a system for viewing and browsing graphs using a software analog of a fisheye lens. We first show how to implement such a view using solely geometric transformations. We then describe a more general transformation that allows global information about the graph to affect the view. Our general transformation is a fundamental extension to previous research in fisheye views. Categories and Subject Descriptors: D.2.2 [Software Engineering]: Tools and TechniquesUser Interfaces H.5.2 [Information Interfaces and Presentation]: User InterfacesInteraction styles I.3.6 [Computer Graphics]: Methodology and TechniquesInteraction Techniques General Terms: Visualization Additional Key Words and Phrases: Fisheye Views, Graph Layout, Information Visualization, Interactive Gra...
A Formal Framework for Linguistic Annotation
 Speech Communication
, 2000
"... `Linguistic annotation' covers any descriptive or analytic notations applied to raw language data. The basic data may be in the form of time functions  audio, video and/or physiological recordings  or it may be textual. The added notations may include transcriptions of all sorts (from phonetic ..."
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Cited by 125 (22 self)
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`Linguistic annotation' covers any descriptive or analytic notations applied to raw language data. The basic data may be in the form of time functions  audio, video and/or physiological recordings  or it may be textual. The added notations may include transcriptions of all sorts (from phonetic features to discourse structures), partofspeech and sense tagging, syntactic analysis, `named entity' identification, coreference annotation, and so on. While there are several ongoing efforts to provide formats and tools for such annotations and to publish annotated linguistic databases, the lack of widely accepted standards is becoming a critical problem. Proposed standards, to the extent they exist, have focused on file formats. This paper focuses instead on the logical structure of linguistic annotations. We survey a wide variety of existing annotation formats and demonstrate a common conceptual core, the annotation graph. This provides a formal framework for constructing, mai...
A fast adaptive layout algorithm for undirected graphs
, 1995
"... Abstract. We present a randomized adaptive layout algorithm for nicely drawing undirected graphs that is based on the springembedder paradigm and contains several new heuristics to improve the convergence, including local temperatures, gravitational forces and the detection of rotations and oscilla ..."
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Cited by 103 (1 self)
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Abstract. We present a randomized adaptive layout algorithm for nicely drawing undirected graphs that is based on the springembedder paradigm and contains several new heuristics to improve the convergence, including local temperatures, gravitational forces and the detection of rotations and oscillations. The proposed algorithm achieves drawings of high quality on a wide range of graphs with standard settings. Moreover, the algorithm is fast, being thus applicable on general undirected graphs of substantially larger size and complexity than before [9, 6, 3]. Aesthetically pleasing solutions are found in most cases. We give empirical data for the running time of the algorithm and the quality of the computed layouts. 1
A Multilevel Algorithm for ForceDirected GraphDrawing
, 2003
"... We describe a heuristic method for drawing graphs which uses a multilevel framework combined with a forcedirected placement algorithm. ..."
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Cited by 89 (3 self)
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We describe a heuristic method for drawing graphs which uses a multilevel framework combined with a forcedirected placement algorithm.
On the Computational Complexity of Upward and Rectilinear Planarity Testing (Extended Abstract)
, 1994
"... A directed graph is upward planar if it can be drawn in the plane such that every edge is a monotonically increasing curve in the vertical direction, and no two edges cross. An undirected graph is rectilinear planar if it can be drawn in the plane such that every edge is a horizontal or vertical se ..."
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Cited by 82 (4 self)
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A directed graph is upward planar if it can be drawn in the plane such that every edge is a monotonically increasing curve in the vertical direction, and no two edges cross. An undirected graph is rectilinear planar if it can be drawn in the plane such that every edge is a horizontal or vertical segment, and no two edges cross. Testing upward planarity and rectilinear planarity are fundamental problems in the effective visualization of various graph and network structures. In this paper we show that upward planarity testing and rectilinear planarity testing are NPcomplete problems. We also show that it is NPhard to approximate the minimum number of bends in a planar orthogonal drawing of an nvertex graph with an O(n 1\Gammaffl ) error, for any ffl ? 0.
Upward Planarity Testing
 SIAM Journal on Computing
, 1995
"... Acyclic digraphs, such as the covering digraphs of ordered sets, are usually drawn upward, i.e., with the edges monotonically increasing in the vertical direction. A digraph is upward planar if it admits an upward planar drawing. In this survey paper, we overview the literature on the problem of upw ..."
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Cited by 81 (15 self)
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Acyclic digraphs, such as the covering digraphs of ordered sets, are usually drawn upward, i.e., with the edges monotonically increasing in the vertical direction. A digraph is upward planar if it admits an upward planar drawing. In this survey paper, we overview the literature on the problem of upward planarity testing. We present several characterizations of upward planarity and describe upward planarity testing algorithms for special classes of digraphs, such as embedded digraphs and singlesource digraphs. We also sketch the proof of NPcompleteness of upward planarity testing.
Visualizing Complex Hypermedia Networks through Multiple Hierarchical Views
, 1995
"... Our work concerns visualizing the information space of hypermedia systems using multiple hierarchical views. Although overview diagrams are useful for helping the user to navigate in a hypermedia system, for any realworld system they become too complicated and large to be really useful. This is bec ..."
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Cited by 80 (2 self)
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Our work concerns visualizing the information space of hypermedia systems using multiple hierarchical views. Although overview diagrams are useful for helping the user to navigate in a hypermedia system, for any realworld system they become too complicated and large to be really useful. This is because these diagrams represent complex network structures which are very difficult to visualize and comprehend. On the other hand, effective visualizations of hierarchies have been developed. Our strategy is to provide the user with different hierarchies, each giving a different perspective to the underlying information space, to help the user better comprehend the information. We propose an algorithm based on content and structural analysis to form hierarchies from hypermedia networks. The algorithm is automatic but can be guided by the user. The multiple hierarchies can be visualized in various ways. We give examples of the implementation of the algorithm on two hypermedia systems.
An Experimental Comparison of Four Graph Drawing Algorithms
, 1995
"... In this paper we present an extensive experimental study comparing four generalpurpose graph drawing algorithms. The four algorithms take as input general graphs (with no restrictions whatsoever on connectivity, planarity, etc.) and construct orthogonal grid drawings, which are widely used in so ..."
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Cited by 62 (9 self)
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In this paper we present an extensive experimental study comparing four generalpurpose graph drawing algorithms. The four algorithms take as input general graphs (with no restrictions whatsoever on connectivity, planarity, etc.) and construct orthogonal grid drawings, which are widely used in software and database visualization applications. The test data (available by anonymous ftp) are 11,582 graphs, ranging from 10 to 100 vertices, which have been generated from a core set of 112 graphs used in "reallife" software engineering and database applications. The experiments