Remove rows with all or some NAs (missing values) in data.frame

Question

I\'d like to remove the lines in this data frame that:

a) contain NAs across all columns. Below is my example data frame.

Answer 1

delete.dirt <- function(DF, dart=c('NA')) {
  dirty_rows <- apply(DF, 1, function(r) !any(r %in% dart))
  DF <- DF[dirty_rows, ]
}

mydata <- delete.dirt(mydata)

Above function deletes all the rows from the data frame that has 'NA' in any column and returns the resultant data. If you want to check for multiple values like NA and ? change dart=c('NA') in function param to dart=c('NA', '?')