[R] Unexpected result after auto-attaching of the Matrix package

[H B]

Dear all,

I just stumbled on this behavior - not sure if this is expected:

R version 4.4.2 (2024-10-31) -- "Pile of Leaves"
Copyright (C) 2024 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu

 > library(Matrix)

 > sparseMatrix(i=1:10, j=1:10, x=rnorm(10)) |>
saveRDS("~/Downloads/sparsemat_test.rds")
 > q()
Save workspace image? [y/n/c]: n
# start R again
 > d <- readRDS("~/Downloads/sparsemat_test.rds")
 > class(d)
[1] "dgCMatrix"
attr(,"package")
[1] "Matrix"
 > dim(d)
Loading required package: Matrix
NULL
 > dim(d)
[1] 10 10

So the first call to dim(d) loads/attaches the Matrix package but
returns NULL for the call. Only the second call to dim returns the
correct results. I would expect the first call to succeed also,
otherwise what is the purpose of loading the package?

Best regards

Hilmar


 > sessionInfo()
R version 4.4.2 (2024-10-31)
Platform: x86_64-pc-linux-gnu
Running under: Ubuntu 24.04.1 LTS

Matrix products: default
BLAS:   /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.12.0
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.12.0

locale:
  [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C
  [3] LC_TIME=de_DE.UTF-8        LC_COLLATE=en_US.UTF-8
  [5] LC_MONETARY=de_DE.UTF-8    LC_MESSAGES=en_US.UTF-8
  [7] LC_PAPER=de_DE.UTF-8       LC_NAME=C
  [9] LC_ADDRESS=C               LC_TELEPHONE=C
[11] LC_MEASUREMENT=de_DE.UTF-8 LC_IDENTIFICATION=C

time zone: Europe/Berlin
tzcode source: system (glibc)

attached base packages:> sessionInfo()
R version 4.4.2 (2024-10-31)
Platform: x86_64-pc-linux-gnu
Running under: Ubuntu 24.04.1 LTS

Matrix products: default
BLAS:   /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.12.0
LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.12.0

locale:
  [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C
  [3] LC_TIME=de_DE.UTF-8        LC_COLLATE=en_US.UTF-8
  [5] LC_MONETARY=de_DE.UTF-8    LC_MESSAGES=en_US.UTF-8
  [7] LC_PAPER=de_DE.UTF-8       LC_NAME=C
  [9] LC_ADDRESS=C               LC_TELEPHONE=C
[11] LC_MEASUREMENT=de_DE.UTF-8 LC_IDENTIFICATION=C

time zone: Europe/Berlin
tzcode source: system (glibc)

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods base

other attached packages:
[1] Matrix_1.7-2

loaded via a namespace (and not attached):
[1] compiler_4.4.2 grid_4.4.2     lattice_0.22-5

[1] stats     graphics  grDevices utils     datasets  methods base

other attached packages:
[1] Matrix_1.7-2

loaded via a namespace (and not attached):
[1] compiler_4.4.2 grid_4.4.2     lattice_0.22-5