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13
The art and science of dynamic network visualization
 Journal of Social Structure
, 2006
"... If graph drawing is to become a methodological tool instead of an illustrative art, many concerns need to be overcome. We discuss the problems of social network visualization, and particularly, problems of dynamic network visualization. We consider issues that arise from the aggregation of continuou ..."
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Cited by 29 (0 self)
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If graph drawing is to become a methodological tool instead of an illustrative art, many concerns need to be overcome. We discuss the problems of social network visualization, and particularly, problems of dynamic network visualization. We consider issues that arise from the aggregation of continuoustime relational data ("streaming " interactions) into a series of networks. We discuss our experience developing SoNIA (Social Network Image Animator,
A Numerical Optimization Approach to General Graph Drawing
, 1999
"... Graphs are ubiquitous, finding applications in domains ranging from software engineering to computational biology. While graph theory and graph algorithms are some of the oldest, most studied fields in computer science, the problem of visualizing graphs is comparatively young. This problem, known as ..."
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Cited by 19 (0 self)
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Graphs are ubiquitous, finding applications in domains ranging from software engineering to computational biology. While graph theory and graph algorithms are some of the oldest, most studied fields in computer science, the problem of visualizing graphs is comparatively young. This problem, known as graph drawing, is that of transforming combinatorial graphs into geometric drawings for the purpose of visualization. Most published algorithms for drawing general graphs model the drawing problem with a physical analogy, representing a graph as a system of springs and other physical elements and then simulating the relaxation of this physical system. Solving the graph drawing problem involves both choosing a physical model and then using numerical optimization to simulate the physical system. In this
DigCoLa: Directed graph layout through constrained energy minimization
 IEEE Symposium on Information Visualization, Infovis’05, 2005
"... We describe a new method for visualization of directed graphs. The method combines constraint programming techniques with a high performance forcedirected placement (FDP) algorithm so that the directed nature of the graph is highlighted while useful properties of FDP — such as emphasis of symmetrie ..."
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Cited by 12 (4 self)
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We describe a new method for visualization of directed graphs. The method combines constraint programming techniques with a high performance forcedirected placement (FDP) algorithm so that the directed nature of the graph is highlighted while useful properties of FDP — such as emphasis of symmetries and preservation of proximity relations — are retained. Our algorithm automatically identifies those parts of the digraph that contain hierarchical information and draws them accordingly. Additionally, those parts that do not contain hierarchy are drawn at the same quality expected from a nonhierarchical, undirected layout algorithm. An interesting application of our algorithm is directional multidimensional scaling (DMDS). DMDS deals with lowdimensional embedding of multivariate data where we want to emphasize the overall flow in the data (e.g. chronological progress) along one of the axes.
Drawing Directed Graphs Using OneDimensional Optimization
 Proc. Graph Drawing 2002, LNCS 2528
, 2001
"... We present an algorithm for drawing directed graphs, which is based on rapidly solving a unique onedimensional optimization problem for each of the axes. The algorithm results in a clear description of the hierarchy structure of the graph. Nodes are not restricted to lie on fixed horizontal laye ..."
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Cited by 9 (6 self)
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We present an algorithm for drawing directed graphs, which is based on rapidly solving a unique onedimensional optimization problem for each of the axes. The algorithm results in a clear description of the hierarchy structure of the graph. Nodes are not restricted to lie on fixed horizontal layers, resulting in layouts that convey the symmetries of the graph very naturally. The algorithm can be applied without change to cyclic or acyclic digraphs, and even to graphs containing both directed and undirected edges. We also derive a hierarchy index from the input digraph, which quantitatively measures its amount of hierarchy.
Drawing directed graphs using quadratic programming
 IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS
, 2006
"... We describe a new method for visualization of directed graphs. The method combines constraint programming techniques with a high performance forcedirected placement (FDP) algorithm. The resulting placements highlight hierarchy in directed graphs while retaining useful properties of FDP; such as em ..."
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Cited by 5 (4 self)
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We describe a new method for visualization of directed graphs. The method combines constraint programming techniques with a high performance forcedirected placement (FDP) algorithm. The resulting placements highlight hierarchy in directed graphs while retaining useful properties of FDP; such as emphasis of symmetries and preservation of proximity relations. Our algorithm automatically identifies those parts of the digraph that contain hierarchical information and draws them accordingly. Additionally, those parts that do not contain hierarchy are drawn at the same quality expected from a nonhierarchical, undirected layout algorithm. Our experiments show that this new approach is better able to convey the structure of large digraphs than the most widely used hierarchical graphdrawing method. An interesting application of our algorithm is directional multidimensional scaling (DMDS). DMDS deals with lowdimensional embedding of multivariate data where we want to emphasize the overall flow in the data (e.g., chronological progress) along one of the axes.
Interactive Graph Drawing on the World Wide Web
 In Sixth World Wide Web Conference
, 1996
"... We discuss a system for performing interactive graph drawing on the World Wide Web (WWW), implemented in the Java programming language. The system allows for highly interactive experimentation in graph drawing, supporting direct user interaction and parameter adjustment during the embedding process. ..."
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Cited by 4 (0 self)
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We discuss a system for performing interactive graph drawing on the World Wide Web (WWW), implemented in the Java programming language. The system allows for highly interactive experimentation in graph drawing, supporting direct user interaction and parameter adjustment during the embedding process. The use of Java and the WWW in its implementation makes the system globally available, both for interactive use and for integration into other systems, regardless of computer platform details. We present the design, implementation and use of the system, as well as some experimental results. 1 Introduction We present a World Wide Web (WWW) based system for interactive experimental graph drawing. The system is written in Java [12], a WWW programming language, and is therefore available for use on almost any computer system connected to the Internet. The system supports a very high degree of user interaction and parameter adjustment, allowing direct interaction with the graph layout during th...
An Improved Springbased Graph Embedding Algorithm and LayoutShow: a Java Environment for Graph Drawing
, 1999
"... Algorithms based on forcedirected placement and virtual physical models have become one of the most effective techniques for drawing undirected graphs. Springbased algorithms that are the subject of this thesis are one type of forcedirected algorithms. Spring algorithms are simple. They produce g ..."
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Cited by 4 (0 self)
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Algorithms based on forcedirected placement and virtual physical models have become one of the most effective techniques for drawing undirected graphs. Springbased algorithms that are the subject of this thesis are one type of forcedirected algorithms. Spring algorithms are simple. They produce graphs with approximately uniform edge lengths, distribute nodes reasonably well, and preserve graph symmetries. A problem with these algorithms is that depending on their initial layout, it is possible that they find undesirable drawings associated with some local minimum criteria. In addition, it has always been a challenge to determine when a layout is stable in order to stop the algorithm. In this thesis, we develop a simple but effective cost function that can determine a node layout quality as well as the quality of the entire graph layout during the execution of a Spring algorithm. We use this cost function for producing the initial layout of the algorithm, for helping nodes move out ...
Graph Layout Techniques and Multidimensional Data Analysis
, 2000
"... In this paper we explore the relationship between multivariate data analysis and techniques for graph drawing or graph layout. Although both classes of techniques were created for quite different purposes, we find many common principles and implementations. We start with a discussion of the data an ..."
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Cited by 4 (0 self)
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In this paper we explore the relationship between multivariate data analysis and techniques for graph drawing or graph layout. Although both classes of techniques were created for quite different purposes, we find many common principles and implementations. We start with a discussion of the data analysis techniques, in particular multiple correspondence analysis, multidimensional scaling, parallel coordinate plotting, and seriation. We then discuss parallels in the graph layout literature.
Drawing Recurrent Hierarchies
, 2012
"... Directed graphs are generally drawn as level drawings using the hierarchical approach. Such drawings are constructed by a framework of algorithms which operates in four phases: cycle removal, leveling, crossing reduction, and coordinate assignment. However, there are situations where cycles should b ..."
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Cited by 2 (2 self)
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Directed graphs are generally drawn as level drawings using the hierarchical approach. Such drawings are constructed by a framework of algorithms which operates in four phases: cycle removal, leveling, crossing reduction, and coordinate assignment. However, there are situations where cycles should be displayed as such, e. g., distinguished cycles in the biosciences and scheduling processes repeating in a daily or weekly turn. In their seminal paper on hierarchical drawings Sugiyama et al. [31] also introduced recurrent hierarchies. This concept supports the drawing of cycles and their unidirectional display. However, it had not been investigated. In this paper we complete the cyclic approach and investigate the coordinate assignment phase. The leveling and the crossing reduction for recurrent hierarchies have been studied in the companion papers [3, 4]. We provide an algorithm which runs in linear time and constructs an intermediate drawing with at most two bends per edge and aligned edge segments in an area of quadratic width times the preset number of levels height. This area bound is optimal for such drawings. Our approach needs new techniques for solving cyclic dependencies, such as skewing edges and cutting components. The drawings can be transformed into 2D drawings displaying all cycles counterclockwise around a center and into 3D drawings winding the cycles around a cylinder.
Automatic Layout of Diagrams in Rational Rose
, 1998
"... : A general overview of the problem of automatically generating aesthetically pleasing drawings of graphs is presented. Requirements particular to diagrams in Rational Rose is discussed. The Sugiyama layout algorithm and the Spring Embedder algorithm together with a number of proposed modifications ..."
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Cited by 1 (0 self)
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: A general overview of the problem of automatically generating aesthetically pleasing drawings of graphs is presented. Requirements particular to diagrams in Rational Rose is discussed. The Sugiyama layout algorithm and the Spring Embedder algorithm together with a number of proposed modifications and improvements to these algorithms are discussed. Examples of drawings generated by these algorithms are presented. Automatic layout of diagrams through the use of genetic algorithms is also discussed. Supervisor: Gunnar Blomberg, Rational Software Scandinavia AB Examiner: Mats Nordstrm, Computing Science Dept., Uppsala University Passed: Contents 1 Introduction 1 1.1 Definition of Terms 2 1.2 Background 3 1.3 Problem Description 4 1.4 General Difficulties 6 2 Different Approaches 7 2.1 Algorithmic Approach 7 2.2 Declarative Approach 8 3 Examples of Algorithmic Approaches 9 3.1 Sugiyama Algorithm 9 3.1.1 Phase 1 Revisited  Preprocessing 10 3.1.2 Phase 2 Revisited  Edge Crossing Mini...