Keep both dataframes' own values only replace at intersection in R

Question

Say I have the following two data-frames and I want to merge them using merge function.

> x <- data.frame(id=c("a", "b", "c"), type=c("good", "ok", "not-ok"))
> y <- data.frame(id=c("b", "d"), type=c("ok", "good"), kind=c("A", "B"))
> merge(x, y, by.x="id", by.y="id", all=TRUE)
  id type.x type.y kind
1  a   good   <NA> <NA>
2  b     ok     ok    A
3  c not-ok   <NA> <NA>
4  d   <NA>   good    B

What I want to get is

  id   type    kind
1  a   good    <NA>
2  b     ok       A
3  c not-ok    <NA>
4  d   good       B

Is there a nice way to do this in R, please? Thanks.

what is wrong with your solution? What do you mean by nice? – Sal-laS Aug 22 '18 at 08:08 — Sal-laS, Aug 22 '18 at 08:08
Try `merge(x, y, all = TRUE)` – markus Aug 22 '18 at 08:11 — markus, Aug 22 '18 at 08:11

FMM · Answer 1 · 2018-08-22T08:29:43.047

In Base R:

merge(x, y, all = TRUE)

With tidyverse:

First, an addition when you are creating your data frame:

x <- data.frame(id=c("a", "b", "c"), type=c("good", "ok", "not-ok"),
                stringsAsFactors = FALSE)

y <- data.frame(id=c("b", "d"), type=c("ok", "good"), kind=c("A", "B"),
                stringsAsFactors = FALSE)

Add stringsAsFactors = FALSE to prevent Warnings in the next step:

library(tidyverse)

df <- full_join(x,y)

Edited based on @markus' comments.

score 1 · Answer 2 · answered Aug 22 '18 at 08:21

1

Easy!

library(dplyr)

x %>% full_join(y, by  = c("id", "type"))

  id   type    kind
1  a   good    <NA>
2  b     ok       A
3  c not-ok    <NA>
4  d   good       B

answered Aug 22 '18 at 08:21

Shinobi_Atobe

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Keep both dataframes' own values only replace at intersection in R

2 Answers2