-1

Suppose I have a data frame (lets call it df) that looks like this (below). I am trying to remove ALL duplicates in a given data frame based on a given column (df$car). 

options(stringsAsFactors=F)
car <- c('car1', 'car2', 'car2', 'car3', 'car4', 'car4', 'car4', 'car5', 'car6', 'car6')
location <- c(111,345,345,123,678,678,678,432,232,232)
value <- c(1,1,1,1,2,2,2,2,4,4)
a <- c('AT','ATC','TAT','C','TT','TGGGG','GGC','CC','AA','AT')
b <- c('A', 'TAG','TAG','G','AA','AA','AA','GG','TT','TT')

df <- data.frame(car,location,value,a,b)


> df
    car    location value   a    b
 1  car1      111     1    AT    A
 2  car2      345     1   ATC  TAG
 3  car2      345     1   TAT  TAG
 4  car3      123     1     C    G
 5  car4      678     2    TT   AA
 6  car4      678     2 TGGGG   AA
 7  car4      678     2   GGC   AA
 8  car5      432     2    CC   GG
 9  car6      232     4    AA   TT
 10 car6      232     4    AT   TT

My desired output is the following. I wish to remove ALL columns that have duplicates, not just the unique values.

    car    location value   a    b
 1  car1      111     1    AT    A
 4  car3      123     1     C    G
 8  car5      432     2    CC   GG

Please note: I believe this is a different question than others that have posted in the past. Most questions are asking for the unique rows based on a given column, but I'm asking that even those rows be removed. If this is a duplicate post, I'm happy to close this one - I just haven't found what I'm looking for yet! Thanks for your help!

Sheila
  • 2,438
  • 7
  • 28
  • 37
  • 1
    Possible duplicate of [How can I remove all duplicates so that NONE are left in a data frame in R?](https://stackoverflow.com/questions/13763216/how-can-i-remove-all-duplicates-so-that-none-are-left-in-a-data-frame-in-r) OR for a specific column as in your case [Extract original and duplicate result(s) from a data frame in R](https://stackoverflow.com/questions/21359904/extract-original-and-duplicate-results-from-a-data-frame-in-r) – Ronak Shah Jun 20 '17 at 05:13

1 Answers1

1

Can you try if this works:

  df[!(duplicated(df$car) | duplicated(df$car, fromLast = TRUE)), ]
AK88
  • 2,946
  • 2
  • 12
  • 31