Fill in missing values with previous or next value

Fills missing values in selected columns using the next or previous entry. This is useful in the common output format where values are not repeated, and are only recorded when they change.

fill(data, ..., .direction = c("down", "up", "downup", "updown"))

Arguments

data	A data frame.
...	A selection of columns. If empty, nothing happens. You can supply bare variable names, select all variables between x and z with x:z, exclude y with -y. For more selection options, see the dplyr::select() documentation.
.direction	Direction in which to fill missing values. Currently either "down" (the default), "up", "downup" (i.e. first down and then up) or "updown" (first up and then down).

Details

Missing values are replaced in atomic vectors; NULLs are replaced in lists.

Examples

df <- data.frame(Month = 1:12, Year = c(2000, rep(NA, 11)))
df %>% fill(Year)
#>    Month Year
#> 1      1 2000
#> 2      2 2000
#> 3      3 2000
#> 4      4 2000
#> 5      5 2000
#> 6      6 2000
#> 7      7 2000
#> 8      8 2000
#> 9      9 2000
#> 10    10 2000
#> 11    11 2000
#> 12    12 2000