I read a post on the R-blogger.
The writer use purrr
's function in this way .
library(tidyverse)
spread <- list(sd = sd, iqr = IQR, mad = mad)
x <- rnorm(100)
invoke_map_dbl(spread, x = x)
#> sd iqr mad
#> 1.040133 1.393010 1.051002
Created on 2018-11-26 by the reprex package (v0.2.1)
Session info
devtools::session_info()
#> - Session info ----------------------------------------------------------
#> setting value
#> version R version 3.5.1 (2018-07-02)
#> os Windows 7 x64 SP 1
#> system x86_64, mingw32
#> ui RTerm
#> language (EN)
#> collate Chinese (Simplified)_People's Republic of China.936
#> ctype Chinese (Simplified)_People's Republic of China.936
#> tz Asia/Taipei
#> date 2018-11-26
#>
#> - Packages --------------------------------------------------------------
#> package * version date lib source
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I read the help document, there is no argument named by x
in it.
invoke_map_dbl(.f, .x = list(NULL), ..., .env = NULL)
I wonder is there any special meanin of x = x
here?