How to remove rows in a dataframe considering there are duplicates in one column of dataframe

Question

Hi dear I have a little problem with a dataframe that has duplicates in a column. I would like to remove the rows where a column presents duplicates. For example my datafram

Answer 1

Use the function duplicated.

Something like:

data.subset <- data[!duplicated(data$ID),]

Duplicated returns a true/false vector. The second duplicated entry in the vector will always return TRUE.