How to delete specific rows with while?

I'm a beginner in R and I need some help:

In my database, very big since I'm working with micro-data, I want to remove some rows when there is a specific value of a Column...i was trying to implement some function to do that....but I'm having a problem with the 开发者_StackOverflow社区IF condition(true/false problem). For example, I want to remove the row i when the column DISC in that line is "L", then i did this function:

dellinhas<-function(x){

  n<-nrow(x)
  i<-1
  while (i<=n) {
  if (x[i,]$DISC=="L") {x<-x[-(i:i),]}
  i<-i+1}
  dadosPrmM<-x
}

Where x is the database. What am I doing wrong?

Use subscripting:

x[x$DISC != "L",]

And try this website for basic data manipulation issues: http://www.statmethods.net/