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I have just added new data to my original data frame, so simplified, it looks like this:

df <- data.frame(ID = rep(letters[1:5], each = 2))
df

ID    Volume
1   a   1.23
2   a   
3   a
4   a
5   b   4.74
6   b
7   b
8   b
9   c   5.35
10  c
11  c
12  c
13  c
14  d   1.53
15  d
16  d

where I have an ID column with differing numbers of entries for each ID and a volume for one entry, but not the others.

Is there a way to populate the empty Volume cells with the filled cell of the corresponding ID?

I'm essentially trying to remove the step of going into Excel and using the "drag to fill" for each ID (I have over 2000 IDs). Not every ID has the same amount of entries (i.e. ID "a" has 4, where ID "c" has 5 and ID "d" has 3).

I'm thinking dplyr will have a tool to do this, but I have not been able to find the answer.

sm925
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EagleEye
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2 Answers2

1

In the tidyverse

library(tidyverse)

df %>% 
  group_by(id) %>% 
  fill()
Bruno
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0

Here is a base R solution, where ave() is used to fill up the NAs

df <- within(df,Volume <- ave(Volume,ID, FUN = function(x) unique(x[!is.na(x)])))
ThomasIsCoding
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