合并R中的两列

Question

I have two columns in R:

Origin    Dest  
ALB       ATL  
ALB       LAG  
ALB       LAX  

I need them to look like this (in one column):

Origin-Dest  
ALB-ATL  
ALB-LAG  
ALB-LAX  

Does anyone know how to combine two lines without getting too complicated?
This is the code I have so far:

air <- read.table(delta, header=T, sep=",")  
aircolSQL <- sqldf("select Origin, Dest, ActualElapsedTime from air")  
airsortSQL <- sqldf("select * from aircolSQL order by Origin asc, Dest")  
airsortSQL$ActualTimeHours = round((airsortSQL$ActualElapsedTime/60),1)  
airsortSQL$ActualElapsedTime <-  NULL 

Thanks!

Answer 1

In SQLite || is used for string concatenation:

library(sqldf)
sqldf("select Origin || '-' || Dest OD from air")

giving:

       OD
1 ALB-ATL
2 ALB-LAG
3 ALB-LAX

data We used this as air :

air <- structure(list(Origin = structure(c(1L, 1L, 1L), .Label = "ALB", 
class = "factor"), Dest = structure(1:3, .Label = c("ATL", "LAG", "LAX"), 
class = "factor")), .Names = c("Origin", "Dest"), class = "data.frame", 
row.names = c(NA, -3L))

Answer 2

If df is your data frame:

df <- data.frame(Origin = rep('ALB', 3), Dest = c('ATL', 'LAG', 'LAX'))

library(tidyr)
unite_(df, '`Origin-Dest`', c('Origin', 'Dest'), sep = "-")

  `Origin-Dest`
1       ALB-ATL
2       ALB-LAG
3       ALB-LAX

Answer 3

I often use paste:

DataFrame$OriginDest<- paste(DataFrame$Origin,DataFrame$Dest, sep = '-')

I find it the least hassle approach.