Split columns in dataframe with NA

Question

I have a df like this:

df <- data.frame(FOO = c(\'A|B|C\', \'A|B\', \'B|C\', \'A\', \'C\'))

> df
    FOO
1 A|B|C
2   A|B
3   B|C
4     A
5            


        

Answer 1

Simply do:

splt <- strsplit(as.character(df$FOO),"\\|")
all_val <- sort(unique(unlist(splt)))
t(sapply(splt,function(x){all_val[!(all_val %in% x)]<-NA;all_val}))


#     [,1] [,2] [,3]
#[1,] "A"  "B"  "C" 
#[2,] "A"  "B"  NA  
#[3,] NA   "B"  "C" 
#[4,] "A"  NA   NA  
#[5,] NA   NA   "C" 

data:

df <- data.frame(FOO = c('A|B|C', 'A|B', 'B|C', 'A', 'C'))

Please note:

My version is base:: (no libraries needed) and general:

It would also work with:

df <- data.frame(FOO = c('A|B|C', 'A|B', 'B|C', 'A', 'C', 'B|D|F'))