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Graph-tool
graph-tool is a Python module for manipulation and statistical analysis of graphs (AKA networks). The core data structures and algorithms of graph-tool are implemented in C++, making extensive use of metaprogramming, based heavily on the Boost Graph Library. Many algorithms are implemented in parallel using OpenMP, which provides increased performance on multi-core architectures. Features * Creation and manipulation of directed or undirected graphs. * Association of arbitrary information to the vertices, edges or even the graph itself, by means of property maps. * Filter vertices and/or edges "on the fly", such that they appear to have been removed. * Support for dot, Graph Modelling Language and GraphML formats. * Convenient and powerful graph drawing based on cairo or Graphviz. * Support for typical statistical measurements: degree/property histogram, combined degree/property histogram, vertex-vertex correlations, assortativity, average vertex-vertex shortest path, etc. * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graph Modelling Language
Graph Modeling Language (GML) is a hierarchical ASCII-based file format for describing graphs. It has been also named ''Graph Meta Language''. Example A simple graph in GML format: graph comment "This is a sample graph" directed 1 id 42 label "Hello, I am a graph" node [ id 1 label "node 1" thisIsASampleAttribute 42 node [ id 2 label "node 2" thisIsASampleAttribute 43 ] node [ id 3 label "node 3" thisIsASampleAttribute 44 ] edge [ source 1 target 2 label "Edge from node 1 to node 2" ] edge [ source 2 target 3 label "Edge from node 2 to node 3" ] edge source 3 target 1 label "Edge from node 3 to node 1" ] Applications supporting GML * Cytoscape, an open source bioinformatics software platform for visualizing molecular interaction networks, loads and save previously-constructed interaction networks in GML. * igraph, an open source network analysis library with interfaces to multiple programming languages. * Gephi, an open sour ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphviz
Graphviz (short for ''Graph Visualization Software'') is a package of open-source tools initiated by AT&T Labs Research for drawing graphs specified in DOT language scripts having the file name extension "gv". It also provides libraries for software applications to use the tools. Graphviz is free software licensed under the Eclipse Public License. Tools ; dot : a command-line tool to produce layered graph drawings in a variety of output formats, such as (PostScript, PDF, SVG, annotated text and so on). ; neato : useful for undirected graphs. "spring model" layout, minimizes global energy. Useful for graphs up to about 1000 nodes ; fdp : force-directed graph drawing similar to "spring model", but minimizes forces instead of energy. Useful for undirected graphs. ; sfdp : multiscale version of fdp for the layout of large undirected graphs ; twopi : for radial graph layouts. Nodes are placed on concentric circles depending their distance from a given root node ; circo : circul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tiago P
Tiago is a given and a family name, being one of the Portuguese equivalents of the names Jacob and James. Its archaic spelling, used mostly in Brazil, is Thiago. Tiago may also refer to: *Tiago (horse) (foaled 2004), an American racehorse * "Tiago" (song), by French singer Kendji Girac from his 2018 album ''Amigo'' *Tata Tiago, an Indian hatchback automobile Places * São Tiago, Brazilian city in the state of Minas * Santiago, Isabela, Philippines * Santiago de Chile, capital and largest city of Chile * Santiago de Compostela, city in Galicia, Spain * Santiago de Cuba, second largest city of Cuba * Santiago de los Caballeros, second largest city of the Dominican Republic * , m any applications People with the given name * Tiago Cardoso (other), many applications of Tiago Cardoso / Thiago Cardoso *Bebé (born 1990), real name Tiago Manuel Dias Correia, Portuguese football player * Tiago (footballer, born 1984), full name Tiago dos Santos Roberto, Brazilian football forw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cairo (graphics)
Cairo (stylized as cairo) is an open-source graphics library that provides a vector graphics-based, device-independent API for software developers. It provides primitives for two-dimensional drawing across a number of different back ends. Cairo uses hardware acceleration when available. Software architecture Language bindings A library written in one programming language may be used in another language if bindings are written; Cairo has a range of bindings for various languages including C++, C# and other CLI languages, Delphi, Eiffel, Factor, Harbour, Haskell, Julia, Lua, Perl, PHP, Python, Ruby, Rust, Scheme, Smalltalk and several others like Gambas (Visual Basic like). Toolkit bindings Since Cairo is only a drawing library, it can be quite useful to integrate it with a graphical user interface toolkit. * FLTK has full Cairo support (through --enable-cairo compile switch). * GTK began in 2005, with version 2.8, to use Cairo to render the majority of its gra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Community Structure
In the study of complex networks, a network is said to have community structure if the nodes of the network can be easily grouped into (potentially overlapping) sets of nodes such that each set of nodes is densely connected internally. In the particular case of ''non-overlapping'' community finding, this implies that the network divides naturally into groups of nodes with dense connections internally and sparser connections between groups. But ''overlapping'' communities are also allowed. The more general definition is based on the principle that pairs of nodes are more likely to be connected if they are both members of the same community(ies), and less likely to be connected if they do not share communities. A related but different problem is community search, where the goal is to find a community that a certain vertex belongs to. Properties In the study of networks, such as computer and information networks, social networks and biological networks, a number of different charac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Network Motif
Network motifs are recurrent and statistically significant Subgraph (graph theory), subgraphs or patterns of a larger complex network, graph. All networks, including biological networks, social networks, technological networks (e.g., computer networks and electrical circuits) and more, can be represented as graphs, which include a wide variety of subgraphs. Network motifs are sub-graphs that repeat themselves in a specific network or even among various networks. Each of these sub-graphs, defined by a particular pattern of interactions between vertices, may reflect a framework in which particular functions are achieved efficiently. Indeed, motifs are of notable importance largely because they may reflect functional properties. They have recently gathered much attention as a useful concept to uncover structural design principles of complex networks. Although network motifs may provide a deep insight into the network's functional abilities, their detection is computationally challengi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clustering Coefficient
In graph theory, a clustering coefficient is a measure of the degree to which nodes in a graph tend to cluster together. Evidence suggests that in most real-world networks, and in particular social networks, nodes tend to create tightly knit groups characterised by a relatively high density of ties; this likelihood tends to be greater than the average probability of a tie randomly established between two nodes (Holland and Leinhardt, 1971; Watts and Strogatz, 1998). Two versions of this measure exist: the global and the local. The global version was designed to give an overall indication of the clustering in the network, whereas the local gives an indication of the embeddedness of single nodes. Local clustering coefficient The local clustering coefficient of a vertex (node) in a graph quantifies how close its neighbours are to being a clique (complete graph). Duncan J. Watts and Steven Strogatz introduced the measure in 1998 to determine whether a graph is a small-world network ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centrality
In graph theory and network analysis, indicators of centrality assign numbers or rankings to nodes within a graph corresponding to their network position. Applications include identifying the most influential person(s) in a social network, key infrastructure nodes in the Internet or urban networks, super-spreaders of disease, and brain networks. Centrality concepts were first developed in social network analysis, and many of the terms used to measure centrality reflect their sociological origin.Newman, M.E.J. 2010. ''Networks: An Introduction.'' Oxford, UK: Oxford University Press. Definition and characterization of centrality indices Centrality indices are answers to the question "What characterizes an important vertex?" The answer is given in terms of a real-valued function on the vertices of a graph, where the values produced are expected to provide a ranking which identifies the most important nodes. The word "importance" has a wide number of meanings, leading to many diffe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maximum Flow
In optimization theory, maximum flow problems involve finding a feasible flow through a flow network that obtains the maximum possible flow rate. The maximum flow problem can be seen as a special case of more complex network flow problems, such as the circulation problem. The maximum value of an s-t flow (i.e., flow from source s to sink t) is equal to the minimum capacity of an s-t cut (i.e., cut severing s from t) in the network, as stated in the max-flow min-cut theorem. History The maximum flow problem was first formulated in 1954 by T. E. Harris and F. S. Ross as a simplified model of Soviet railway traffic flow. In 1955, Lester R. Ford, Jr. and Delbert R. Fulkerson created the first known algorithm, the Ford–Fulkerson algorithm.Ford, L.R., Jr.; Fulkerson, D.R., ''Flows in Networks'', Princeton University Press (1962). In their 1955 paper, Ford and Fulkerson wrote that the problem of Harris and Ross is formulated as follows (see p. 5):Consider a rail network conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dominator (graph Theory)
In computer science, a node of a control-flow graph dominates a node if every path from the ''entry node'' to must go through . Notationally, this is written as (or sometimes ). By definition, every node dominates itself. There are a number of related concepts: * A node ''strictly dominates'' a node if dominates and does not equal . * The ''immediate dominator'' or idom of a node is the unique node that strictly dominates but does not strictly dominate any other node that strictly dominates . Every node, except the entry node, has an immediate dominator. * The ''dominance frontier'' of a node is the set of all nodes such that dominates an immediate predecessor of , but does not strictly dominate . It is the set of nodes where 's dominance stops. * A ''dominator tree'' is a tree where each node's children are those nodes it immediately dominates. The start node is the root of the tree. History Dominance was first introduced by Reese T. Prosser in a 1959 paper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connected Component (graph Theory)
In graph theory, a component of an undirected graph is a connected subgraph that is not part of any larger connected subgraph. The components of any graph partition its vertices into disjoint sets, and are the induced subgraphs of those sets. A graph that is itself connected has exactly one component, consisting of the whole graph. Components are sometimes called connected components. The number of components in a given graph is an important graph invariant, and is closely related to invariants of matroids, topological spaces, and matrices. In random graphs, a frequently occurring phenomenon is the incidence of a giant component, one component that is significantly larger than the others; and of a percolation threshold, an edge probability above which a giant component exists and below which it does not. The components of a graph can be constructed in linear time, and a special case of the problem, connected-component labeling, is a basic technique in image analysis. Dynamic co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minimum Spanning Tree
A minimum spanning tree (MST) or minimum weight spanning tree is a subset of the edges of a connected, edge-weighted undirected graph that connects all the vertices together, without any cycles and with the minimum possible total edge weight. That is, it is a spanning tree whose sum of edge weights is as small as possible. More generally, any edge-weighted undirected graph (not necessarily connected) has a minimum spanning forest, which is a union of the minimum spanning trees for its connected components. There are many use cases for minimum spanning trees. One example is a telecommunications company trying to lay cable in a new neighborhood. If it is constrained to bury the cable only along certain paths (e.g. roads), then there would be a graph containing the points (e.g. houses) connected by those paths. Some of the paths might be more expensive, because they are longer, or require the cable to be buried deeper; these paths would be represented by edges with larger weights ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
