Wide to long to wide (Abby)

mwe.R

# this solves the data wrangling problem described at:
# https://twitter.com/AbbyCScience/status/1205549666567368705?s=20

library(tidyverse)
library(lubridate)

dat <- tibble(
   ID = 1:4,
   event_1 = c(mdy("1/1/17"), mdy("2/14/18"), mdy("10/30/17"), mdy("6/10/18")),
   event_2 = c(mdy("1/1/17"), mdy("2/14/18"), NA, NA),
   event_3 = c(mdy(NA), NA, mdy("12/16/17"), mdy("6/10/18")),
   event_4 = c(mdy("12/31/16"), NA, NA, mdy("6/19/18")),
   event_5 = c(mdy(NA), mdy("2/14/18"), mdy("10/30/17"), mdy("6/10/18")),
   event_6 = c(mdy("12/31/16"), mdy("2/14/18"), mdy("1/1/18"), NA)
)
   
dat %>% 
   pivot_longer(-ID) %>%
   group_by(ID) %>%
   arrange(ID, value) %>%
   filter(!is.na(value)) %>%
   mutate(time = str_sub(name, -1),
          event = c("first_event", "second_event", "third_event", "fourth_event")) %>%
   select(ID, time, event) %>%
   pivot_wider(
      names_from = event,
      values_from = time
   )