What happens, and what did you expect instead?
graph_from_adjacency_matrix() trips if matrix has dimnames. I think they could be safely ignored. In other words, is_symmetric() might be too strict.
To reproduce
library(igraph)
m <- matrix(
c(0, 1, 1, 0),
2, 2,
dimnames=list(r=1:2, c=1:2)
)
graph_from_adjacency_matrix(m, mode = "undirected") # warning because this is FALSE:
isSymmetric(m)
# I believe atrtibutes could be safely ignored:
isSymmetric(m, check.attributes = FALSE) # Uses all.equal() internally
System information
─ Session info ─────────────────────────────────────────────────────────────────────────────────
setting value
version R version 4.6.0 (2026-04-24)
os Ubuntu 24.04.4 LTS
system x86_64, linux-gnu
ui RStudio
language en
collate en_US.UTF-8
ctype en_US.UTF-8
tz Europe/Warsaw
date 2026-05-26
rstudio 2026.04.0+526 Globemaster Allium (desktop)
pandoc 3.1.3 @ /usr/bin/pandoc
quarto 1.9.37 @ /usr/local/bin/quarto
─ Packages ─────────────────────────────────────────────────────────────────────────────────────
package * version date (UTC) lib source
cli 3.6.6 2026-04-09 [1] CRAN (R 4.6.0)
igraph * 2.3.1 2026-05-04 [1] CRAN (R 4.6.0)
lifecycle 1.0.5 2026-01-08 [1] CRAN (R 4.6.0)
magrittr 2.0.5 2026-04-04 [1] CRAN (R 4.6.0)
pkgconfig 2.0.3 2019-09-22 [1] CRAN (R 4.6.0)
rlang 1.2.0 2026-04-06 [1] CRAN (R 4.6.0)
rstudioapi 0.18.0 2026-01-16 [1] CRAN (R 4.6.0)
sessioninfo 1.2.3 2025-02-05 [1] CRAN (R 4.6.0)
[1] /home/mbojan/R/library/4.6
[2] /usr/local/lib/R/site-library
[3] /usr/lib/R/site-library
[4] /usr/lib/R/library
* ── Packages attached to the search path.
What happens, and what did you expect instead?
graph_from_adjacency_matrix()trips if matrix has dimnames. I think they could be safely ignored. In other words,is_symmetric()might be too strict.To reproduce
System information