given NA values fill them with the next non-na value

given NA values fill them with the next non-na value

fill_backward(x)

Arguments

x	A numeric vector of values

Details

Works very well in context of dplyr to carry out backwards imputation

Examples

fill_backward(c(1.0, NA, 2))
#> [1] 1 2 2
fill_backward(c(NA, 1, NA, 2))
#> [1] 1 1 2 2
library(dplyr)
df <- data_frame(id = c(1, 1, 2, 2), obs = c(1.2, 4.8, 2.5, NA))
df %>% group_by(id) %>% mutate(obs_imp = fill_backward(obs))
#> # A tibble: 4 x 3
#> # Groups:   id [2]
#>      id   obs obs_imp
#>   <dbl> <dbl>   <dbl>
#> 1     1   1.2     1.2
#> 2     1   4.8     4.8
#> 3     2   2.5     2.5
#> 4     2  NA      NA