Working in matlab and I don't know how to use .csv files any help with that on this problem would be appreciated

3.4 csvio.m . Modify cavio.m so that the function reads in a .cav file containing the identification number and three (3) quiz scores for a collection of n students and computes a n x 1 vector of each student's average . Write the identification numbers, quiz grades, and averages back to the file