Combine vectors of different lengths

[joelnitta]

Hello!

I have a step in a targets plan where I want to combine vectors that are the result of branching. If func_that_returns_vec below returned a vector of length 1, this works, but it doesn't if the vector is longer.

How can I make this work?

Thanks!

targets::tar_dir({
  targets::tar_script({
    library(targets)
    
    func_that_returns_vec <- function(param, name) {
      c(
        paste0(param, name, "first-item"),
        paste0(param, name, "second-item")
      )
    }
    
    list(
      tar_target(x_params, c(1,2)),
      tar_target(x_names, c("x-a","x-b")),
      tar_target(y_params, c(3,4)),
      tar_target(y_names, c("y-a","y-b")),
      tar_target(
        x_results,
        func_that_returns_vec(x_params, x_names),
        pattern = map(x_params, x_names),
      ),
      tar_target(
        y_results,
        func_that_returns_vec(y_params, y_names),
        pattern = map(y_params, y_names)
      ),
      tar_target(
        all_results,
        c(x_results, y_results)
      )
    )
    
  })
  
  targets::tar_make()
  
})
#> ● run target y_names
#> ● run target y_params
#> ● run target x_params
#> ● run target x_names
#> ● run branch y_results_f7f07863
#> ● run branch y_results_1638369d
#> ● run branch x_results_6178c7d5
#> ● run branch x_results_a1bf677f
#> ● run target all_results
#> Error : Can't merge the outer name `x_results_6178c7d5` with a vector of length > 1.
#> Please supply a `.name_spec` specification.
#> Error: callr subprocess failed: Can't merge the outer name `x_results_6178c7d5` with a vector of length > 1.
#> Please supply a `.name_spec` specification.

^{Created on 2021-02-20 by the reprex package (v1.0.0)}

Session info

sessioninfo::session_info()
#> ─ Session info ───────────────────────────────────────────────────────────────
#>  setting  value                       
#>  version  R version 4.0.3 (2020-10-10)
#>  os       macOS Catalina 10.15.7      
#>  system   x86_64, darwin17.0          
#>  ui       X11                         
#>  language (EN)                        
#>  collate  en_US.UTF-8                 
#>  ctype    en_US.UTF-8                 
#>  tz       Asia/Tokyo                  
#>  date     2021-02-20                  
#> 
#> ─ Packages ───────────────────────────────────────────────────────────────────
#>  package     * version date       lib source        
#>  assertthat    0.2.1   2019-03-21 [1] CRAN (R 4.0.0)
#>  callr         3.5.1   2020-10-13 [1] CRAN (R 4.0.2)
#>  cli           2.3.0   2021-01-31 [1] CRAN (R 4.0.2)
#>  codetools     0.2-18  2020-11-04 [1] CRAN (R 4.0.2)
#>  crayon        1.4.1   2021-02-08 [1] CRAN (R 4.0.3)
#>  data.table    1.13.6  2020-12-30 [1] CRAN (R 4.0.2)
#>  digest        0.6.27  2020-10-24 [1] CRAN (R 4.0.2)
#>  ellipsis      0.3.1   2020-05-15 [1] CRAN (R 4.0.0)
#>  evaluate      0.14    2019-05-28 [1] CRAN (R 4.0.0)
#>  fs            1.5.0   2020-07-31 [1] CRAN (R 4.0.2)
#>  glue          1.4.2   2020-08-27 [1] CRAN (R 4.0.2)
#>  highr         0.8     2019-03-20 [1] CRAN (R 4.0.0)
#>  htmltools     0.5.1.1 2021-01-22 [1] CRAN (R 4.0.2)
#>  igraph        1.2.6   2020-10-06 [1] CRAN (R 4.0.2)
#>  knitr         1.31    2021-01-27 [1] CRAN (R 4.0.2)
#>  lifecycle     1.0.0   2021-02-15 [1] CRAN (R 4.0.3)
#>  magrittr      2.0.1   2020-11-17 [1] CRAN (R 4.0.2)
#>  pillar        1.4.7   2020-11-20 [1] CRAN (R 4.0.2)
#>  pkgconfig     2.0.3   2019-09-22 [1] CRAN (R 4.0.0)
#>  processx      3.4.5   2020-11-30 [1] CRAN (R 4.0.2)
#>  ps            1.5.0   2020-12-05 [1] CRAN (R 4.0.2)
#>  purrr         0.3.4   2020-04-17 [1] CRAN (R 4.0.0)
#>  R6            2.5.0   2020-10-28 [1] CRAN (R 4.0.2)
#>  reprex        1.0.0   2021-01-27 [1] CRAN (R 4.0.2)
#>  rlang         0.4.10  2020-12-30 [1] CRAN (R 4.0.2)
#>  rmarkdown     2.6     2020-12-14 [1] CRAN (R 4.0.2)
#>  rstudioapi    0.13    2020-11-12 [1] CRAN (R 4.0.2)
#>  sessioninfo   1.1.1   2018-11-05 [1] CRAN (R 4.0.0)
#>  stringi       1.5.3   2020-09-09 [1] CRAN (R 4.0.2)
#>  stringr       1.4.0   2019-02-10 [1] CRAN (R 4.0.0)
#>  targets       0.1.0   2021-02-01 [1] CRAN (R 4.0.2)
#>  tibble        3.0.6   2021-01-29 [1] CRAN (R 4.0.2)
#>  tidyselect    1.1.0   2020-05-11 [1] CRAN (R 4.0.0)
#>  vctrs         0.3.6   2020-12-17 [1] CRAN (R 4.0.2)
#>  withr         2.4.1   2021-01-26 [1] CRAN (R 4.0.2)
#>  xfun          0.20    2021-01-06 [1] CRAN (R 4.0.2)
#>  yaml          2.2.1   2020-02-01 [1] CRAN (R 4.0.0)
#> 
#> [1] /Library/Frameworks/R.framework/Versions/4.0/Resources/library

[wlandau]

Thanks for sharing, you found a bug. Should be fixed now. Please try 142708d.

[wlandau]

The previous commit had a bug of its own. Please try the next subsequent commit that passes CI checks.

[wlandau]

A more minimal example _targets.R that reproduces this:

# _targets.R
library(targets)
list(
  tar_target(x, seq_len(2)),
  tar_target(y, rep(x, 2), pattern = map(x)),
  tar_target(z, y)
)

[joelnitta]

Thanks! Seems fixed in 598d7a2.