similar to: Weighted Graph Link strength ( I am making mistake please help)

I am getting some unexpected results from some functions of igraph and it is possible that I am misinterpreting the vertex numbers. Eg., the max betweenness measure seems to be from a vertex that is not connected to a single other vertex. Below if my code snippet: require(igraph) my.graph <- graph.adjacency(adjmatrix = my.adj.matrix, mode=c("undirected")) most.between.vert <-

Hello All, I went through lot of searching for papers to do clustering on Co-Authroship.I ran SNA metrics on my Undirected Graph(betweenness,Closeness,Eigen Vector) using R. After running the sna Metrics I found important nodes and did clustering on those nodes based on Binding strength .This clustering is done through if they are connected.I would like to do clustering based on Weight of the

Hello, I am calculating 'Betweenness' of a large network using R. Currently, I have the node-node information (City1-City2) in an excel file, present in two columns where column A has City1 and column B has City2 that city1 is connected to. These are the steps that I go through to calculate betweenness of my network. a) Convert the City1-City2 (text) into Number1-Number2 in the excel

I would like to apply network measures (such as betweenness centrality, upper boundedness, etc.) to a weighted graph with non-integer weights, defined by a euclidean distance matrix. The package sna provides the measures that I want to use, but seems only to operate on binary graphs. I have read work by Mark Newman (http://aps.arxiv.org/abs/cond-mat/0407503/), who suggests that a weighted graph

Dear users, I am stucked with a programming problem: I am trying to download a squared adjacency matrix from matlab with only 0 or 1. Doing it without a loop at first, I get an error message that is, I think, related to the "mat_adj<-readMat(pathnames_adj)" line. Did anybodz encouter already that problem? If so, do I need to change anything in my code in order it not to be

Hello all, I'm having a spot of trouble. I have made a very nice distance matrix from some comparison calculations. However, the matrix is 3096 x 3096, so it's relatively large. Currently I'm using the svn package as it seems to work for my data. The graph package errors and says the "adjacency matrix must be symmetric for undirected graphs". I though 3096 x 3096 was

Hi everyone, I have successfully created and analyzed my network data. I am new to R, and Network Analysis too, but I want to color my vertex based on some of the centrality measures calculated. Can someone point me in the right direction? Again, I am new to R, but given how powerful R appears to be, I figure this is probably pretty easy to do, I just wish I could figure it out. Many thanks

Hello, I am working with graph and adjacency matrix, the package 'graph' seems to be appropriate for this. An example in the package > mat <- rbind(c(0, 0, 1, 1), + c(0, 0, 1, 1), + c(1, 1, 0, 1), + c(1, 1, 1, 0)) > rownames(mat) <- colnames(mat) <- letters[1:4] > graph1 <- new("graphAM", adjMat=mat) > graph1 A

Hi, I have a data set consisting of the x and y coordinate locations of 1600 points. I would like to generate a graph using the functions in igraph. However the graph making functions in igraph requires the data to be in the form of an adjacency matrix. I'd like some advice on how to convert my point pattern to an adjacency matrix or functions out there that would do it directly. I've

Hi all, I'm very new to R and read a few tutorials, however I'm having difficulty trying to figure out how to plot a minimum spanning tree. I have a csv file that contains an n-by-n matrix of distances between strains of bacteria called matrix.csv. Looks like: id,strain1, strain2,strain3 strain1,0,.2,.8 strain2,.3,0,.7 strain3,.4,.6,0 I've been messing around with some information

I have created an adjacency matrix but have not been able to figure something out. I need to put zeros on the diagonal of the adjacency matrix. For instance, location (i,i) to equal 0. Please help. Thanks -- View this message in context: http://r.789695.n4.nabble.com/Adjacency-Matrix-help-tp3740946p3740946.html Sent from the R help mailing list archive at Nabble.com.

> > Hello All, > Please help me with this problem.I have been having this problem for over a month now and I could not find any information.I later realised that error is with MATRIX package. I am working on graph object using IGRAPH version 0.5.2-2 package & wanted to do Bonacich Power. What I have is undirected GRAPH. This is my graph object. The file 'Bonacich

Hi everyone, I'm writting a script that will open multiple files in a single folder and then will do some calculations to finally save everything in a big table. So here is the pseudo code #read all files in the given directory myfiles <-list.files("c:\\myDir") #initialize table ??? #loop through files for(f in myfiles[-1]) { netMat <-

Hello, I apologise if someone has already answered this but I searched and googled but didn't find anything. I have a matrix which gives me the similarity of each item to each other. I would like to turn this matrix into something like what they have in the graph package with the nodes and edges. http://cran.r-project.org/doc/packages/graph.pdf . However I cannot find a method to

Dear R users I'm a novice user of R and have absolutely no prior knowledge of social network analysis, so apologies if my question is trivial. I've spent alot of time trying to solve this on my own but I really can't so hope someone here can help me out. Cheers! The dataset: I'm trying to predict the existance of links (True or False) in a test set using a training set. Both

Estimados, estoy ?jugando? con unos datos clínicos donde realizo un análisis de redes, utilicé igraph como nerwork, pero finalmente uso igraph (creo que tiene más opciónes). Son algo de 200 nodos y algo más de 2000 relaciones. Puedo graficarlos. Los datos están de la siguiente forma, por ejemplo, individuo, patología, (las dos primeras columnas son la relación), luego un fármaco, el grupo

I represent a graph as an adjacency matrix of class "dgCMatrix" (from the Matrix package). > xx 5 x 5 sparse Matrix of class "dgCMatrix" a b c d e a . 1 1 . . b 1 . 1 . . c 1 1 . 1 1 d . . 1 . 1 e . . 1 1 . To check if the matrix defines and undirected graph, I have made the following functions/methods: is.UG <- function (object) { UseMethod("is.UG") }

Hi all, A while ago there was a discussion on changing the current "set of trees" representation of TBAA metadata to be more expressive, prompted by the need to support C structs. Dan Gohman also talked about the issue here: http://llvm.org/devmtg/2012-11/Gohman-AliasAnalysis.pdf. It was suggested that the trees be replaced by a type DAG then. While working on this compiler

Dear All, I hope I am not asking a FAQ. I am dealing with a problem of graph theory [connected components in a non-directed graph] and I do not want to rediscover the wheel. I saw a large number of R packages dealing for instance with the k-means method or hierarchical clustering for spatially distributed data and I am basically facing a similar problem. I am given a set of data which are the

Dear R-users, These days, I have been struggling to install the package sna on my Ubuntu 8.04 laptop. My R version is currently R 2.7.2. And I had no trouble installing any other packages (including network). However when I run 'install.packages("sna")', compilation of C codes is ok, but a syntax error is reported when building help pages and sna does not want to install. I