Loop over an empty data frame in R and assign values to columns

Question

With the help of the following code I want to define an empty dataframe which is having 5 number of columns and then as you can see with the help of for loop I am assigning values to each and every column.

k = 1:5

dfk = data.frame(k1 = c(), k2 = c(), k3 = c(), k4 = c(), k5 = c())

for (j in 1:5){

    for (i in 1:12){

        dfk[j] = c(dfk[j], i+j)

    }

    plot(1:12, dfk[j])

}

I am getting the following error:

"Error in [.data.frame(dfk, j): undefined columns selected Traceback: 1. dfk[j] 2. [.data.frame(dfk, j) 3. stop("undefined columns selected")"

Answer 1

Your way of performing that is correct but you have used too many c(). Kindly refer to the following code that will help you in achieving that output:

dfk = data.frame(matrix(ncol = 5, nrow = 0))

colnames(dfk) <- c("k1","k2","k3","k4","k5")

for (j in 1:5){

  for (i in 1:12){

    dfk[i,j] = i+j

  }

  plot(1:12, dfk[,j])

}

If you are a beginner and want to know more about R then do refer to the R programming tutorial that will you in a better way.