[R] Help needed in reading matlab files

[Rui Barradas]

Sorry, it's
adj_con <- file(pathnames_adj, open = "rb")

Rui Barradas
Em 14-08-2012 19:12, Rui Barradas escreveu:
> Hello,
>
> I don't have MATLAB here so this is completely untested but the help 
> page for readMat says:
>
>
>      Arguments
>
> |con|
>
> Binary |connection 
> <http://127.0.0.1:11101/library/base/html/connections.html>| to which 
> the MAT file structure should be written to. A string is interpreted 
> as filename, which then will be opened (and closed afterwards).
>
>
> So it should recognize a filename and open it as a binary connection. 
> If it doesn't, try
>
> adj_con <- file(pathnames_adj, open = "b")
> mat_adj <- readMat(adj_con)
> [...etc...]
> close(adj_con)
>
> Hope this helps,
>
> Rui Barradas
>
> Em 14-08-2012 12:54, jerome at kosta.ch escreveu:
>> 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 at 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.
>