How to add header to a dataset in R?

You can also use colnames instead of names if you have data.frame or matrix

You can also solve this problem by creating an array of values and assigning that array:

newheaders <- c("a", "b", "c", ... "x")
colnames(data) <- newheaders

You can do the following:

Load the data:

test <- read.csv(
          "http://archive.ics.uci.edu/ml/machine-learning-databases/breast-cancer-wisconsin/breast-cancer-wisconsin.data",
          header=FALSE)

Note that the default value of the header argument for read.csv is TRUE so in order to get all lines you need to set it to FALSE.

Add names to the different columns in the data.frame

names(test) <- c("A","B","C","D","E","F","G","H","I","J","K")

or alternative and faster as I understand (not reloading the entire dataset):

colnames(test) <- c("A","B","C","D","E","F","G","H","I","J","K")