Lecture 23 Beyond Force-Directed Layout
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Networkx Tutorial
5.03.2020 tutorial NetworkX tutorial Source: https://github.com/networkx/notebooks (https://github.com/networkx/notebooks) Minor corrections: JS, 27.02.2019 Creating a graph Create an empty graph with no nodes and no edges. In [1]: import networkx as nx In [2]: G = nx.Graph() By definition, a Graph is a collection of nodes (vertices) along with identified pairs of nodes (called edges, links, etc). In NetworkX, nodes can be any hashable object e.g. a text string, an image, an XML object, another Graph, a customized node object, etc. (Note: Python's None object should not be used as a node as it determines whether optional function arguments have been assigned in many functions.) Nodes The graph G can be grown in several ways. NetworkX includes many graph generator functions and facilities to read and write graphs in many formats. To get started though we'll look at simple manipulations. You can add one node at a time, In [3]: G.add_node(1) add a list of nodes, In [4]: G.add_nodes_from([2, 3]) or add any nbunch of nodes. An nbunch is any iterable container of nodes that is not itself a node in the graph. (e.g. a list, set, graph, file, etc..) In [5]: H = nx.path_graph(10) file:///home/szwabin/Dropbox/Praca/Zajecia/Diffusion/Lectures/1_intro/networkx_tutorial/tutorial.html 1/18 5.03.2020 tutorial In [6]: G.add_nodes_from(H) Note that G now contains the nodes of H as nodes of G. In contrast, you could use the graph H as a node in G. -
Networkx: Network Analysis with Python
NetworkX: Network Analysis with Python Salvatore Scellato Full tutorial presented at the XXX SunBelt Conference “NetworkX introduction: Hacking social networks using the Python programming language” by Aric Hagberg & Drew Conway Outline 1. Introduction to NetworkX 2. Getting started with Python and NetworkX 3. Basic network analysis 4. Writing your own code 5. You are ready for your project! 1. Introduction to NetworkX. Introduction to NetworkX - network analysis Vast amounts of network data are being generated and collected • Sociology: web pages, mobile phones, social networks • Technology: Internet routers, vehicular flows, power grids How can we analyze this networks? Introduction to NetworkX - Python awesomeness Introduction to NetworkX “Python package for the creation, manipulation and study of the structure, dynamics and functions of complex networks.” • Data structures for representing many types of networks, or graphs • Nodes can be any (hashable) Python object, edges can contain arbitrary data • Flexibility ideal for representing networks found in many different fields • Easy to install on multiple platforms • Online up-to-date documentation • First public release in April 2005 Introduction to NetworkX - design requirements • Tool to study the structure and dynamics of social, biological, and infrastructure networks • Ease-of-use and rapid development in a collaborative, multidisciplinary environment • Easy to learn, easy to teach • Open-source tool base that can easily grow in a multidisciplinary environment with non-expert users -
Graph Database Fundamental Services
Bachelor Project Czech Technical University in Prague Faculty of Electrical Engineering F3 Department of Cybernetics Graph Database Fundamental Services Tomáš Roun Supervisor: RNDr. Marko Genyk-Berezovskyj Field of study: Open Informatics Subfield: Computer and Informatic Science May 2018 ii Acknowledgements Declaration I would like to thank my advisor RNDr. I declare that the presented work was de- Marko Genyk-Berezovskyj for his guid- veloped independently and that I have ance and advice. I would also like to thank listed all sources of information used Sergej Kurbanov and Herbert Ullrich for within it in accordance with the methodi- their help and contributions to the project. cal instructions for observing the ethical Special thanks go to my family for their principles in the preparation of university never-ending support. theses. Prague, date ............................ ........................................... signature iii Abstract Abstrakt The goal of this thesis is to provide an Cílem této práce je vyvinout webovou easy-to-use web service offering a database službu nabízející databázi neorientova- of undirected graphs that can be searched ných grafů, kterou bude možno efektivně based on the graph properties. In addi- prohledávat na základě vlastností grafů. tion, it should also allow to compute prop- Tato služba zároveň umožní vypočítávat erties of user-supplied graphs with the grafové vlastnosti pro grafy zadané uži- help graph libraries and generate graph vatelem s pomocí grafových knihoven a images. Last but not least, we implement zobrazovat obrázky grafů. V neposlední a system that allows bulk adding of new řadě je také cílem navrhnout systém na graphs to the database and computing hromadné přidávání grafů do databáze a their properties. -
Graphprism: Compact Visualization of Network Structure
GraphPrism: Compact Visualization of Network Structure Sanjay Kairam, Diana MacLean, Manolis Savva, Jeffrey Heer Stanford University Computer Science Department {skairam, malcdi, msavva, jheer}@cs.stanford.edu GraphPrism Connectivity ABSTRACT nodeRadius 7.9 strokeWidth 1.12 charge -242 Visual methods for supporting the characterization, com- gravity 0.65 linkDistance 20 parison, and classification of large networks remain an open Transitivity updateGraph Close Controls challenge. Ideally, such techniques should surface useful 0 node(s) selected. structural features { such as effective diameter, small-world properties, and structural holes { not always apparent from Density either summary statistics or typical network visualizations. In this paper, we present GraphPrism, a technique for visu- Conductance ally summarizing arbitrarily large graphs through combina- tions of `facets', each corresponding to a single node- or edge- specific metric (e.g., transitivity). We describe a generalized Jaccard approach for constructing facets by calculating distributions of graph metrics over increasingly large local neighborhoods and representing these as a stacked multi-scale histogram. MeetMin Evaluation with paper prototypes shows that, with minimal training, static GraphPrism diagrams can aid network anal- ysis experts in performing basic analysis tasks with network Created by Sanjay Kairam. Visualization using D3. data. Finally, we contribute the design of an interactive sys- Figure 1: GraphPrism and node-link diagrams for tem using linked selection between GraphPrism overviews the largest component of a co-authorship graph. and node-link detail views. Using a case study of data from a co-authorship network, we illustrate how GraphPrism fa- compactly summarizing networks of arbitrary size. Graph- cilitates interactive exploration of network data. -
Gephi Tools for Network Analysis and Visualization
Frontiers of Network Science Fall 2018 Class 8: Introduction to Gephi Tools for network analysis and visualization Boleslaw Szymanski CLASS PLAN Main Topics • Overview of tools for network analysis and visualization • Installing and using Gephi • Gephi hands-on labs Frontiers of Network Science: Introduction to Gephi 2018 2 TOOLS OVERVIEW (LISTED ALPHABETICALLY) Tools for network analysis and visualization • Computing model and interface – Desktop GUI applications – API/code libraries, Web services – Web GUI front-ends (cloud, distributed, HPC) • Extensibility model – Only by the original developers – By other users/developers (add-ins, modules, additional packages, etc.) • Source availability model – Open-source – Closed-source • Business model – Free of charge – Commercial Frontiers of Network Science: Introduction to Gephi 2018 3 TOOLS CINET CyberInfrastructure for NETwork science • Accessed via a Web-based portal (http://cinet.vbi.vt.edu/granite/granite.html) • Supported by grants, no charge for end users • Aims to provide researchers, analysts, and educators interested in Network Science with an easy-to-use cyber-environment that is accessible from their desktop and integrates into their daily work • Users can contribute new networks, data, algorithms, hardware, and research results • Primarily for research, teaching, and collaboration • No programming experience is required Frontiers of Network Science: Introduction to Gephi 2018 4 TOOLS Cytoscape Network Data Integration, Analysis, and Visualization • A standalone GUI application -
Graph Simplification and Interaction
Graph Clarity, Simplification, & Interaction http://i.imgur.com/cW19IBR.jpg https://www.reddit.com/r/CableManagement/ Today • Today’s Reading: Lombardi Graphs – Bezier Curves • Today’s Reading: Clustering/Hierarchical edge Bundling – Definition of Betweenness Centrality • Emergency Management Graph Visualization – Sean Kim’s masters project • Reading for Tuesday & Homework 3 • Graph Interaction Brainstorming Exercise "Lombardi drawings of graphs", Duncan, Eppstein, Goodrich, Kobourov, Nollenberg, Graph Drawing 2010 • Circular arcs • Perfect angular resolution (edges for equal angles at vertices) • Arcs only intersect 2 vertices (at endpoints) • (not required to be crossing free) • Vertices may be constrained to lie on circle or concentric circles • People are more patient with aesthetically pleasing graphs (will spend longer studying to learn/draw conclusions) • What about relaxing the circular arc requirement and allowing Bezier arcs? • How does it scale to larger data? • Long curved arcs can be much harder to follow • Circular layout of nodes is often very good! • Would like more pseudocode Cubic Bézier Curve • 4 control points • Curve passes through first & last control point • Curve is tangent at P0 to (P1-P0) and at P3 to (P3-P2) http://www.e-cartouche.ch/content_reg/carto http://www.webreference.com/dla uche/graphics/en/html/Curves_learningObject b/9902/bezier.html 2.html “Force-directed Lombardi-style graph drawing”, Chernobelskiy et al., Graph Drawing 2011. • Relaxation of the Lombardi Graph requirements • “straight-line segments -
Constraint Graph Drawing
Constrained Graph Drawing Dissertation zur Erlangung des akademischen Grades des Doktors der Naturwissenschaften vorgelegt von Barbara Pampel, geb. Schlieper an der Universit¨at Konstanz Mathematisch-Naturwissenschaftliche Sektion Fachbereich Informatik und Informationswissenschaft Tag der mundlichen¨ Prufung:¨ 14. Juli 2011 1. Referent: Prof. Dr. Ulrik Brandes 2. Referent: Prof. Dr. Michael Kaufmann II Teile dieser Arbeit basieren auf Ver¨offentlichungen, die aus der Zusammenar- beit mit anderen Wissenschaftlerinnen und Wissenschaftlern entstanden sind. Zu allen diesen Inhalten wurden wesentliche Beitr¨age geleistet. Kapitel 3 (Bachmaier, Brandes, and Schlieper, 2005; Brandes and Schlieper, 2009) Kapitel 4 (Brandes and Pampel, 2009) Kapitel 6 (Brandes, Cornelsen, Pampel, and Sallaberry, 2010b) Zusammenfassung Netzwerke werden in den unterschiedlichsten Forschungsgebieten zur Repr¨asenta- tion relationaler Daten genutzt. Durch geeignete mathematische Methoden kann man diese Netzwerke als Graphen darstellen. Ein Graph ist ein Gebilde aus Kno- ten und Kanten, welche die Knoten verbinden. Hierbei k¨onnen sowohl die Kan- ten als auch die Knoten weitere Informationen beinhalten. Diese Informationen k¨onnen den einzelnen Elementen zugeordnet sein, sich aber auch aus Anordnung und Verteilung der Elemente ergeben. Mit Algorithmen (strukturierten Reihen von Arbeitsanweisungen) aus dem Gebiet des Graphenzeichnens kann man die unterschiedlichsten Informationen aus verschiedenen Forschungsbereichen visualisieren. Graphische Darstellungen k¨onnen das -
Gephi-Poster-Sunbelt-July10.Pdf
The Open Graph Viz Platform Gephi is a new open-source network visualization platform. It aims to create a sustainable software and technical Download Gephi at ecosystem, driven by a large international open-source community, who shares common interests in networks and http://gephi.org complex systems. The rendering engine can handle networks larger than 100K elements and guarantees responsiveness. Designed to make data navigation and manipulation easy, it aims to fulll the complete chain from data importing to aesthetics renements and interaction. Particular focus is made on the software usability and interoperability with other tools. A lot of eorts are made to facilitate the community growth, by providing tutorials, plug-ins development documentation, support and student projects. Current developments include Dynamic Network Analysis (DNA) and Goals spigots (Emails, Twitter, Facebook …) import. Create the Photoshop of network visualization, by combining a rich set of Gephi aims at being built-in features and a sustainable, open to friendly user interface. many kind of users, and creating a large, Design a modular and international and extensible software diverse open-source architecture, facilitate plug-ins development, community reuse and mashup. Build a large, international Features Highlight and diverse open-source community. Community Join the network, participate designing the roadmap, get help to quickly code plug-ins or simply share your ideas. Select, move, paint, resize, connect, group Just with the mouse Export in SVG/PDF to include your infographics Metrics Architecture * Betweenness, Eigenvector, Closeness The modular architecture allows developers adding and extending features * Eccentricity with ease by developing plug-ins. Gephi can also be used as Java library in * Diameter, Average Shortest Path other applications and build for instance, a layout server. -
Plantuml Language Reference Guide (Version 1.2021.2)
Drawing UML with PlantUML PlantUML Language Reference Guide (Version 1.2021.2) PlantUML is a component that allows to quickly write : • Sequence diagram • Usecase diagram • Class diagram • Object diagram • Activity diagram • Component diagram • Deployment diagram • State diagram • Timing diagram The following non-UML diagrams are also supported: • JSON Data • YAML Data • Network diagram (nwdiag) • Wireframe graphical interface • Archimate diagram • Specification and Description Language (SDL) • Ditaa diagram • Gantt diagram • MindMap diagram • Work Breakdown Structure diagram • Mathematic with AsciiMath or JLaTeXMath notation • Entity Relationship diagram Diagrams are defined using a simple and intuitive language. 1 SEQUENCE DIAGRAM 1 Sequence Diagram 1.1 Basic examples The sequence -> is used to draw a message between two participants. Participants do not have to be explicitly declared. To have a dotted arrow, you use --> It is also possible to use <- and <--. That does not change the drawing, but may improve readability. Note that this is only true for sequence diagrams, rules are different for the other diagrams. @startuml Alice -> Bob: Authentication Request Bob --> Alice: Authentication Response Alice -> Bob: Another authentication Request Alice <-- Bob: Another authentication Response @enduml 1.2 Declaring participant If the keyword participant is used to declare a participant, more control on that participant is possible. The order of declaration will be the (default) order of display. Using these other keywords to declare participants -
Chapter 18 Spectral Graph Drawing
Chapter 18 Spectral Graph Drawing 18.1 Graph Drawing and Energy Minimization Let G =(V,E)besomeundirectedgraph.Itisoftende- sirable to draw a graph, usually in the plane but possibly in 3D, and it turns out that the graph Laplacian can be used to design surprisingly good methods. n Say V = m.Theideaistoassignapoint⇢(vi)inR to the vertex| | v V ,foreveryv V ,andtodrawaline i 2 i 2 segment between the points ⇢(vi)and⇢(vj). Thus, a graph drawing is a function ⇢: V Rn. ! 821 822 CHAPTER 18. SPECTRAL GRAPH DRAWING We define the matrix of a graph drawing ⇢ (in Rn) as a m n matrix R whose ith row consists of the row vector ⇥ n ⇢(vi)correspondingtothepointrepresentingvi in R . Typically, we want n<m;infactn should be much smaller than m. Arepresentationisbalanced i↵the sum of the entries of every column is zero, that is, 1>R =0. If a representation is not balanced, it can be made bal- anced by a suitable translation. We may also assume that the columns of R are linearly independent, since any basis of the column space also determines the drawing. Thus, from now on, we may assume that n m. 18.1. GRAPH DRAWING AND ENERGY MINIMIZATION 823 Remark: Agraphdrawing⇢: V Rn is not required to be injective, which may result in! degenerate drawings where distinct vertices are drawn as the same point. For this reason, we prefer not to use the terminology graph embedding,whichisoftenusedintheliterature. This is because in di↵erential geometry, an embedding always refers to an injective map. The term graph immersion would be more appropriate. -
Performing Knowledge Requirements Analysis for Public Organisations in a Virtual Learning Environment: a Social Network Analysis
chnology Te & n S o o ti ft a w a m r r e Fontenele et al., J Inform Tech Softw Eng 2014, 4:2 o f E Journal of n n I g f i o n DOI: 10.4172/2165-7866.1000134 l e a e n r r i n u g o J ISSN: 2165-7866 Information Technology & Software Engineering Research Article Open Access Performing Knowledge Requirements Analysis for Public Organisations in a Virtual Learning Environment: A Social Network Analysis Approach Fontenele MP1*, Sampaio RB2, da Silva AIB2, Fernandes JHC2 and Sun L1 1University of Reading, School of Systems Engineering, Whiteknights, Reading, RG6 6AH, United Kingdom 2Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, DF, 70910-900, Brasil Abstract This paper describes an application of Social Network Analysis methods for identification of knowledge demands in public organisations. Affiliation networks established in a postgraduate programme were analysed. The course was ex- ecuted in a distance education mode and its students worked on public agencies. Relations established among course participants were mediated through a virtual learning environment using Moodle. Data available in Moodle may be ex- tracted using knowledge discovery in databases techniques. Potential degrees of closeness existing among different organisations and among researched subjects were assessed. This suggests how organisations could cooperate for knowledge management and also how to identify their common interests. The study points out that closeness among organisations and research topics may be assessed through affiliation networks. This opens up opportunities for ap- plying knowledge management between organisations and creating communities of practice. -
A Comparative Analysis of Large-Scale Network Visualization Tools
A Comparative Analysis of Large-scale Network Visualization Tools Md Abdul Motaleb Faysal and Shaikh Arifuzzaman Department of Computer Science, University of New Orleans New Orleans, LA 70148, USA. Email: [email protected], [email protected] Abstract—Network (Graph) is a powerful abstraction for scalability for large network analysis. Such study will help a representing underlying relations and structures in large complex person to decide which tool to use for a specific case based systems. Network visualization provides a convenient way to ex- on his need. plore and study such structures and reveal useful insights. There exist several network visualization tools; however, these vary in One such study in [3] compares a couple of tools based on terms of scalability, analytics feature, and user-friendliness. Due scalability. Comparative studies on other visualization metrics to the huge growth of social, biological, and other scientific data, should be conducted to let end users have freedom in choosing the corresponding network data is also large. Visualizing such the specific tool he needs to use. In this paper, we have chosen large network poses another level of difficulty. In this paper, we five widely used visualization tools for an empirical and identify several popular network visualization tools and provide a comparative analysis based on the features and operations comparative analysis. Our comparisons are based on factors these tools support. We demonstrate empirically how those tools such as supported file formats, scalability in visualization scale to large networks. We also provide several case studies of and analysis, interacting capability with the drawn network, visual analytics on large network data and assess performances end user-friendliness (e.g., users with no programming back- of the tools.