[R-sig-Geo] Question on symmetric for nb2mat

[Andrea Gilardi]

Dear all, probably I'm missing something obvious but I have a question on
the matrix built using nb2mat with argument style = "B". More precisely, I
don't understand why the following code says that the matrix *W* (which
should be a binary first-order adjacency matrix) is not symmetric:













*library(spdep)library(rgdal)library(Matrix)# datanc.sids <-
readOGR(system.file("shapes/sids.shp", package = "spData"))adj <-
poly2nb(nc.sids)W <- as(nb2mat(adj, style = "B"),
"Matrix")Matrix::isSymmetric(W)#> [1] FALSEchol(W)#> Error in
asMethod(object): not a symmetric matrix; consider forceSymmetric() or
symmpart()*

Kind regards
Andrea

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