Split into train and test

Now that we have a dataframe, we can apply standard techniques for modeling. In this exercise, you will split the data into training and test sets.

100 XP

To ensure the reproducibility of your results, set a seed to 7, using set.seed().
Use the sample() function to sample two-thirds of the numbers from the sequence from the range of the total number of rows in studentnetworkdata. Name this vector index_train.
Create the training set by including the rows of studentnetworkdata that are stored in index_train and name it training_set.
Create the test set by excluding the rows of studentnetworkdata that are stored in index_train and name it test_set.