error retrieving diagonal from rectangular matrix

[BertvanderVeen]

Greta overloads the R base diag function, but the greta version does not seem to function as advertised; it should extract the main diagonal of a rectangular matrix but instead throws an error. Example from https://greta-stats.org/reference/extract-replace-combine.html below.

x <- greta::as_data(matrix(1:12, 3, 4))
#> ℹ Initialising python and checking dependencies, this may take a moment.
#> ✔ Initialising python and checking dependencies ... done!
#> 
x[1:3, ]
#> greta array (operation)
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    1    4    7   10
#> [2,]    2    5    8   11
#> [3,]    3    6    9   12
x[, 2:4] <- 1:9
e <- greta::diag(x)
#> Error: diagonal elements can only be extracted from square matrices

[njtierney]

Hi @BertvanderVeen - thanks for posting this issue

I confirm this behaviour and also compare it to base R:

mat <- matrix(1:12, 3, 4)

greta_mat <- greta::as_data(mat)
#> ℹ Initialising python and checking dependencies, this may take a moment.
#> ✔ Initialising python and checking dependencies ... done!
#> 

greta_mat[1:3, ]
#> greta array (operation)
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    1    4    7   10
#> [2,]    2    5    8   11
#> [3,]    3    6    9   12

mat[1:3, ]
#>      [,1] [,2] [,3] [,4]
#> [1,]    1    4    7   10
#> [2,]    2    5    8   11
#> [3,]    3    6    9   12

mat[, 2:4] <- 1:9
mat
#>      [,1] [,2] [,3] [,4]
#> [1,]    1    1    4    7
#> [2,]    2    2    5    8
#> [3,]    3    3    6    9

greta_mat[, 2:4] <- 1:9
greta_mat
#> greta array (operation)
#> 
#>      [,1] [,2] [,3] [,4]
#> [1,]    1    1    4    7
#> [2,]    2    2    5    8
#> [3,]    3    3    6    9

diag(mat)
#> [1] 1 2 6

greta::diag(greta_mat)
#> Error: diagonal elements can only be extracted from square matrices

^{Created on 2023-02-08 with reprex v2.0.2}

Session info

``` r sessioninfo::session_info() #> ─ Session info ─────────────────────────────────────────────────────────────── #> setting value #> version R version 4.2.2 (2022-10-31) #> os macOS Ventura 13.2 #> system aarch64, darwin20 #> ui X11 #> language (EN) #> collate en_US.UTF-8 #> ctype en_US.UTF-8 #> tz Australia/Hobart #> date 2023-02-08 #> pandoc 2.19.2 @ /Applications/RStudio.app/Contents/Resources/app/quarto/bin/tools/ (via rmarkdown) #> #> ─ Packages ─────────────────────────────────────────────────────────────────── #> package * version date (UTC) lib source #> base64enc 0.1-3 2015-07-28 [1] CRAN (R 4.2.0) #> callr 3.7.3 2022-11-02 [1] CRAN (R 4.2.0) #> cli 3.6.0 2023-01-09 [1] CRAN (R 4.2.0) #> coda 0.19-4 2020-09-30 [1] CRAN (R 4.2.0) #> codetools 0.2-19 2023-02-01 [1] CRAN (R 4.2.0) #> crayon 1.5.2 2022-09-29 [1] CRAN (R 4.2.0) #> digest 0.6.31 2022-12-11 [1] CRAN (R 4.2.0) #> ellipsis 0.3.2 2021-04-29 [1] CRAN (R 4.2.0) #> evaluate 0.20 2023-01-17 [1] CRAN (R 4.2.0) #> fastmap 1.1.0 2021-01-25 [1] CRAN (R 4.2.0) #> fs 1.6.0 2023-01-23 [1] CRAN (R 4.2.0) #> future 1.31.0 2023-02-01 [1] CRAN (R 4.2.0) #> globals 0.16.2 2022-11-21 [1] CRAN (R 4.2.1) #> glue 1.6.2 2022-02-24 [1] CRAN (R 4.2.0) #> greta 0.4.3.9000 2023-02-06 [1] local #> here 1.0.1 2020-12-13 [1] CRAN (R 4.2.0) #> hms 1.1.2 2022-08-19 [1] CRAN (R 4.2.0) #> htmltools 0.5.4 2022-12-07 [1] CRAN (R 4.2.0) #> jsonlite 1.8.4 2022-12-06 [1] CRAN (R 4.2.0) #> knitr 1.42 2023-01-25 [1] CRAN (R 4.2.0) #> lattice 0.20-45 2021-09-22 [1] CRAN (R 4.2.2) #> lifecycle 1.0.3 2022-10-07 [1] CRAN (R 4.2.0) #> listenv 0.9.0 2022-12-16 [1] CRAN (R 4.2.0) #> magrittr 2.0.3 2022-03-30 [1] CRAN (R 4.2.0) #> Matrix 1.5-3 2022-11-11 [1] CRAN (R 4.2.0) #> parallelly 1.34.0 2023-01-13 [1] CRAN (R 4.2.0) #> pkgconfig 2.0.3 2019-09-22 [1] CRAN (R 4.2.0) #> png 0.1-8 2022-11-29 [1] CRAN (R 4.2.0) #> prettyunits 1.1.1 2020-01-24 [1] CRAN (R 4.2.0) #> processx 3.8.0 2022-10-26 [1] CRAN (R 4.2.0) #> progress 1.2.2 2019-05-16 [1] CRAN (R 4.2.0) #> ps 1.7.2 2022-10-26 [1] CRAN (R 4.2.0) #> purrr 1.0.1 2023-01-10 [1] CRAN (R 4.2.0) #> R.cache 0.16.0 2022-07-21 [1] CRAN (R 4.2.0) #> R.methodsS3 1.8.2 2022-06-13 [1] CRAN (R 4.2.0) #> R.oo 1.25.0 2022-06-12 [1] CRAN (R 4.2.0) #> R.utils 2.12.2 2022-11-11 [1] CRAN (R 4.2.0) #> R6 2.5.1 2021-08-19 [1] CRAN (R 4.2.0) #> Rcpp 1.0.10 2023-01-22 [1] CRAN (R 4.2.0) #> reprex 2.0.2 2022-08-17 [1] CRAN (R 4.2.0) #> reticulate 1.28 2023-01-27 [1] CRAN (R 4.2.0) #> rlang 1.0.6 2022-09-24 [1] CRAN (R 4.2.0) #> rmarkdown 2.20 2023-01-19 [1] CRAN (R 4.2.0) #> rprojroot 2.0.3 2022-04-02 [1] CRAN (R 4.2.0) #> rstudioapi 0.14 2022-08-22 [1] CRAN (R 4.2.0) #> sessioninfo 1.2.2 2021-12-06 [1] CRAN (R 4.2.0) #> styler 1.9.0 2023-01-15 [1] CRAN (R 4.2.0) #> tensorflow 2.11.0 2022-12-19 [1] CRAN (R 4.2.0) #> tfruns 1.5.1 2022-09-05 [1] CRAN (R 4.2.0) #> vctrs 0.5.2 2023-01-23 [1] CRAN (R 4.2.0) #> whisker 0.4.1 2022-12-05 [1] CRAN (R 4.2.0) #> withr 2.5.0 2022-03-03 [1] CRAN (R 4.2.0) #> xfun 0.37 2023-01-31 [1] CRAN (R 4.2.0) #> yaml 2.3.7 2023-01-23 [1] CRAN (R 4.2.0) #> #> [1] /Library/Frameworks/R.framework/Versions/4.2-arm64/Resources/library #> #> ─ Python configuration ─────────────────────────────────────────────────────── #> python: /Users/nick/Library/r-miniconda-arm64/envs/greta-env-tf2/bin/python #> libpython: /Users/nick/Library/r-miniconda-arm64/envs/greta-env-tf2/lib/libpython3.8.dylib #> pythonhome: /Users/nick/Library/r-miniconda-arm64/envs/greta-env-tf2:/Users/nick/Library/r-miniconda-arm64/envs/greta-env-tf2 #> version: 3.8.15 | packaged by conda-forge | (default, Nov 22 2022, 08:49:06) [Clang 14.0.6 ] #> numpy: /Users/nick/Library/r-miniconda-arm64/envs/greta-env-tf2/lib/python3.8/site-packages/numpy #> numpy_version: 1.23.2 #> tensorflow: /Users/nick/Library/r-miniconda-arm64/envs/greta-env-tf2/lib/python3.8/site-packages/tensorflow #> #> NOTE: Python version was forced by use_python function #> #> ────────────────────────────────────────────────────────────────────────────── ```

@goldingn was there any particular reason that this was only allowed to work for square matrices with greta arrays?

[njtierney]

I've confirmed with @goldingn that we should mimic R's behaviour - so we will fix this to act as such.