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 recurrent? If I run the code a second time, it works fine, but this does not help me, as I try to set up a loop for 265 matlab adj matrix, each number representing a specific week and the purpose being to have metrics from igraph being generated over the 265 weeks.
Thank you CODE to read the file: rm(list=ls()) library(R.matlab) path<-setwd("V:/2012/nonweighted_GOVSOV") pattern_adj<-sprintf("weightmatrix1.mat") pathnames_adj<-list.files(pattern=pattern_adj,path=path,full.names=T) cat("Reading MAT file: ", basename(pathnames_adj), "\n", sep="") mat_adj<-readMat(pathnames_adj) adj<-do.call(rbind,mat_adj) library(igraph) g<-graph.adjacency(adj, mode=c("directed"), weighted=T) _______________________________________________________________________ R RESPONSE: > path<-setwd("V:/2012/nonweighted_GOVSOV") > pattern_adj<-sprintf("weightmatrix1.mat") > pathnames_adj<-list.files(pattern=pattern_adj,path=path,full.names=T) > cat("Reading MAT file: ", basename(pathnames_adj), "\n", sep="") Reading MAT file: > mat_adj<-readMat(pathnames_adj) Error in file(con, open = "rb") : invalid 'description' argument > adj<-do.call(rbind,mat_adj) Error in do.call(rbind, mat_adj) : object 'mat_adj' not found > library(igraph) Attaching package: ‘igraph’ The following object(s) are masked from ‘package:R.oo’: hierarchy > g<-graph.adjacency(adj, mode=c("directed"), weighted=T) Error in inherits(adjmatrix, "Matrix") : object 'adj' not found ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.