what is the purpose of nh how do you construct a subset dataframe r ________ is a vector derived from column groups. how to make a logical vector in r how to construct logical vector in r r create subset data frame how to construct a subset dataframe in r r create subset data frame how to db subsets if drawdata is not a subset, it is called what is drawdata$db how to do a subset dataframe in r r create a subset of the dataframe how to make a subset from a dataframe subset dataframe nh which of the following is logical vector derived from column groups? r: subset data frame how to make a subset dataframe which data frame would be a subset of an observation dataset? how to make dataframe in r