matlab tutorial

Simple Network Analysis with MatLabGergana BounovaESD.342February 23, 2006Gergana BounovaESD.342 Feb 23, 2006MatLab Basics Official MathWorks tutorial: http://www.mathworks.com/academia/student_center/tutorials/launchpad.html List of all MatLab functions http://www.mathworks.com/support/functions/alpha_list.html Search by name, topic, description MatLab prompt:>> date>> help ‘what’>> lookfor ‘something’>> help lookforLOOKFOR Search all M-files for keyword.See also dir, help, who, what, which.>> diary (filename,on,off)>> load mydata.mat>> type filename.m (.txt) Loading data: ExcelLink, etcGergana BounovaESD.342 Feb 23, 2006Working Example: Bike References: Daniel Whitney, “Degree Correlations and Motifs in Technological Networks”, Source: http://esd.mit.edu/WPS/esd-wp-2005-10.pdfGergana BounovaESD.342 Feb 23, 2006Graph Representation in MatLab Depends on what you are going to do! Computation, extracting data/properties, visualization… Adjacency matrix A node by node (nxn), if i and j are connected A(i,j)=1, otherwise A(i,j)=0; for multiple edges A(i,j)=2,3,… sum(A) = graph degree sequence (self-loops give an exception) Incidence matrix C node by edge (nxm), if node i is an endpoint for edge j, then C(i,j)=1, otherwise C(i,j)=0 sum(C) = [2 2 2 …2] – every edge has 2 endpointsT Cool formula: A = CxC - 2I List: every node points to the nodes it’s connected to Text: for other programs input (Pajek)Gergana ...