multiple lags

jetlag.Rmd

``` r
library(purrr)
library(dplyr)
#> 
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union

jetlag <- function(data, x, n=10){
  x <- enquo(x)
  
  indices <- seq_len(n)
  quosures <- map( indices, ~quo(lag(!!x, !!.x)) ) %>% 
    set_names(sprintf("lag_%02d", indices))
  
  mutate( data, !!!quosures )
  
}
d <- data_frame(x = seq_len(100))
jetlag(d, x, n=10)
#> # A tibble: 100 x 11
#>        x lag_01 lag_02 lag_03 lag_04 lag_05 lag_06 lag_07 lag_08 lag_09
#>    <int>  <int>  <int>  <int>  <int>  <int>  <int>  <int>  <int>  <int>
#>  1     1     NA     NA     NA     NA     NA     NA     NA     NA     NA
#>  2     2      1     NA     NA     NA     NA     NA     NA     NA     NA
#>  3     3      2      1     NA     NA     NA     NA     NA     NA     NA
#>  4     4      3      2      1     NA     NA     NA     NA     NA     NA
#>  5     5      4      3      2      1     NA     NA     NA     NA     NA
#>  6     6      5      4      3      2      1     NA     NA     NA     NA
#>  7     7      6      5      4      3      2      1     NA     NA     NA
#>  8     8      7      6      5      4      3      2      1     NA     NA
#>  9     9      8      7      6      5      4      3      2      1     NA
#> 10    10      9      8      7      6      5      4      3      2      1
#> # ... with 90 more rows, and 1 more variable: lag_10 <int>
```