spread_help

> head(amelt)
  jdate year   variable      value
1   227 2013 pred_short   7.737878
2   247 2013 pred_short  38.029255
3   269 2013 pred_short 114.233338
4   237 2013 pred_short  64.805227
5   257 2013 pred_short 154.760291
6   284 2013 pred_short  88.092093

I want to have this

jdate 2013 2014 2015
227
247
...

filled with the median value for each combination . 

can't spread() do that? 

I don't have the full dataset so I'm not sure how many combinations there are or if jdate is repeated, but try something like:

amelt %>%
  group_by(year, variable) %>%
  summarize(median = median(value)) %>%
  spread("year", "median")

Does that help?

Forgot the preamble:

library(magrittr)
import::from(tidyr, spread)
import::from(dplyr, group_by, summarize)