casting SpatRaster -> stars -> SpatRaster with time

[btupper]

I think this may be related to this issue, but it might just be operator error. I'm helping to make the tidysdm R package work with both terra and stars but I'm hitting a snag.

I'm looking to make a round trip excursion starting with a single attribute SpatRaster with time bands. The conversion to stars works as expected, but getting back to the original SpatRaster leaves me scratching my head. Is there a trick to converting a single attribute multi-layer stars object to the same as a SpatRaster?

The example below is an adaption of the one used in the earlier issue.

library(terra)
#> terra 1.7.78
library(stars)
#> Loading required package: abind
#> Loading required package: sf
#> Linking to GEOS 3.11.0, GDAL 3.5.3, PROJ 9.1.0; sf_use_s2() is TRUE
s <- rast(system.file("ex/logo.tif", package="terra"))   
time(s) <- as.Date("2001-05-04") + 0:2
ss <- c(s, s)
time(ss) <- as.Date("2001-05-04") + 0:5
(x <- c(ss[[1:3]], ss[[1:2]]))
#> class       : SpatRaster 
#> dimensions  : 77, 101, 5  (nrow, ncol, nlyr)
#> resolution  : 1, 1  (x, y)
#> extent      : 0, 101, 0, 77  (xmin, xmax, ymin, ymax)
#> coord. ref. : Cartesian (Meter) 
#> sources     : logo.tif  (3 layers) 
#>               logo.tif  (2 layers) 
#> names       : red, green, blue, red, green 
#> min values  :   0,     0,    0,   0,     0 
#> max values  : 255,   255,  255, 255,   255 
#> time (days) : 2001-05-04 to 2001-05-06
(s = st_as_stars(x))
#> stars object with 3 dimensions and 1 attribute
#> attribute(s):
#>                           Min. 1st Qu. Median     Mean 3rd Qu. Max.
#> red.green.blue.red.green     0     136    203 185.6155     254  255
#> dimension(s):
#>      from  to offset delta            refsys point                    values
#> x       1 101      0     1 Cartesian (Meter) FALSE                      NULL
#> y       1  77     77    -1 Cartesian (Meter) FALSE                      NULL
#> time    1   5     NA    NA              Date    NA 2001-05-04,...,2001-05-05
#>      x/y
#> x    [x]
#> y    [y]
#> time
as(s, "SpatRaster")
#> class       : SpatRaster 
#> dimensions  : 77, 101, 5  (nrow, ncol, nlyr)
#> resolution  : 1, 1  (x, y)
#> extent      : 0, 101, 0, 77  (xmin, xmax, ymin, ymax)
#> coord. ref. : Cartesian (Meter) 
#> source(s)   : memory
#> names       : time2001-05-04, time2001-05-05, time2001-05-06, time2001-05-04, time2001-05-05 
#> min values  :              0,              0,              0,              0,              0 
#> max values  :            255,            255,            255,            255,            255
sessionInfo()
#> R version 4.4.1 (2024-06-14)
#> Platform: x86_64-apple-darwin20
#> Running under: macOS Sonoma 14.6.1
#> 
#> Matrix products: default
#> BLAS:   /Library/Frameworks/R.framework/Versions/4.4-x86_64/Resources/lib/libRblas.0.dylib 
#> LAPACK: /Library/Frameworks/R.framework/Versions/4.4-x86_64/Resources/lib/libRlapack.dylib;  LAPACK version 3.12.0
#> 
#> locale:
#> [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
#> 
#> time zone: America/New_York
#> tzcode source: internal
#> 
#> attached base packages:
#> [1] stats     graphics  grDevices utils     datasets  methods   base     
#> 
#> other attached packages:
#> [1] stars_0.6-6  sf_1.0-17    abind_1.4-8  terra_1.7-78
#> 
#> loaded via a namespace (and not attached):
#>  [1] cli_3.6.3          knitr_1.48         rlang_1.1.4        xfun_0.48         
#>  [5] DBI_1.2.3          KernSmooth_2.23-24 glue_1.8.0         htmltools_0.5.8.1 
#>  [9] e1071_1.7-16       rmarkdown_2.28     grid_4.4.1         evaluate_1.0.0    
#> [13] classInt_0.4-10    fastmap_1.2.0      yaml_2.3.10        lifecycle_1.0.4   
#> [17] compiler_4.4.1     codetools_0.2-20   fs_1.6.4           Rcpp_1.0.13       
#> [21] rstudioapi_0.16.0  digest_0.6.37      class_7.3-22       reprex_2.1.1      
#> [25] parallel_4.4.1     magrittr_2.0.3     tools_4.4.1        withr_3.0.1       
#> [29] proxy_0.4-27       units_0.8-5

^{Created on 2024-10-09 with reprex v2.1.1}

Cheers,
Ben

[btupper]

Wow! The ink was still wet! Thank you!