Average of column for values of other columns

I have a matrix containing a:locations, b:dayoftheweek, c:hour, d:quarter e: intensities

I need average intensities per each quarter, for each unique location, day and hour.

My data

location day hour quarter intensity
   240    1   0     1        18
   240    1   0     1        26
   240    6   7     3        23
   240    28  22    1        9
   242    5   15    2        35
   240    1   0     1        14

etc

So i would like to make a script that would find mean(18,26,14)=19,33

Is there a more efficient way to do this compared to a loop?

Answer 1

[KL]

data = [240    1   0     1        18
   240    1   0     1        26
   240    6   7     3        23
   240    28  22    1        9
   242    5   15    2        35
   240    1   0     1        14];

res = accumarray(data(data(:,1)==240,4),data(data(:,1)==240,5),[],@mean)

Robust way to deal with such data is to use tables or timetables