Matching multiple columns on different data frames and getting other column as result
Use merge
df1 <- read.table(text=' chr init
1 12 25289552
2 3 180418785
3 3 180434779', header=TRUE)
df2 <- read.table(text=' V1 V2 V3
10 1 69094 medium
11 1 69094 medium
12 12 25289552 high
13 1 69095 medium
14 3 180418785 medium
15 3 180434779 low', header=TRUE)
merge(df1, df2, by.x='init', by.y='V2') # this works!
init chr V1 V3
1 25289552 12 12 high
2 180418785 3 3 medium
3 180434779 3 3 low
To get your desired output the way you show it
output <- merge(df1, df2, by.x='init', by.y='V2')[, c(2,1,4)]
colnames(output)[3] <- 'Mut'
output
chr init Mut
1 12 25289552 high
2 3 180418785 medium
3 3 180434779 low
df1 <- read.table(textConnection(" chr init
1 12 25289552
2 3 180418785
3 3 180434779"), header=T)
df2 <- read.table(textConnection(" V1 V2 V3
10 1 69094 medium
11 1 69094 medium
12 12 25289552 high
13 1 69095 medium
14 3 180418785 medium
15 3 180434779 low"), header=T)
# You have to select the values of df2$V3 such as their corresponding V2
# are equal to the values of df1$init
df1$Mut <- df2$V3[ df2$V2 %in% df1$init]
df1
chr init Mut
1 12 25289552 high
2 3 180418785 medium
3 3 180434779 low