combine rows in data frame containing NA to make complete row

Question

I know this is a duplicate Q but I can\'t seem to find the post again

Using the following data

df <- data.frame(A=c(1,1,2,2),B=c(NA,2,NA,4),C=c(3,         


        

Answer 1

We can use fill to fill all the missing values. And then filter just one row for each group.

library(dplyr)
library(tidyr)

df2 <- df %>%
  group_by(A) %>%
  fill(everything(), .direction = "down") %>%
  fill(everything(), .direction = "up") %>%
  slice(1)