Creating empty data frame

The easiest way to create a null object.

We can use {} to create a NULL object

Simple example, use in for loop.

df <- {}

for (i in 1:10){

  tbl <- c(paste('loop', i, sep='-'))

  df <- rbind(df,tbl)

}

End result is like this,

But if you want to define the columns,

df <- data.frame(matrix(ncol = 3, nrow = 0)) 

colnames(df) <- c("name", "school", "grade")