i have a matrix of 269712x1 double with each cell having values of precipitation for 2hr intervals say 1-3,2-4,3-5....i want to get the max value of the precipitation from the cells for each 365 days...

my data is upto 30 years i.e i will be getting 30 values in total which would be the max value of precipitation corresponding each year...what would be the program for that ? i am just a new learner with not that much of in depth knowledge....any help would be appreciated p.s the matrix 269712x1 btw comes from 24*365*30 x1