How to sort table according to multiple columns at a time?

Question

I have table with 16 columns, first three are input columns. I want to sort whole table according to first three columns at a time.

T = table(a1, a2, a3, ..., a16)

All a1, a2, and a3 will be sorted in ascending order.
For example:

a1 = [6 3 9 6 3 9 6 5]' 
a2 = [7 8 2 3 7 7 6 7]' 
a3 = [9 2 3 3 4 3 7 4]'

The output shall be:

a1 = [3 3 5 6 6 6 9 9]'
a2 = [7 8 7 3 6 7 2 7]'
a3 = [4 2 4 3 7 9 3 3]'

Answer 1

I think the function you are looking for is sortrows. e.g.

a1 = [6 3 9 6 3 9 6 5]';
a2 = [7 8 2 3 7 7 6 7]';
a3 = [9 2 3 3 4 3 7 4]';
temp = table(a1,a2,a3);
sortrows(temp,[1,2,3])

where you supply a vector of the columns you want to sort by.

This gives you

ans =
  8×3 table
    a1    a2    a3
    __    __    __
    3     7     4 
    3     8     2 
    5     7     4 
    6     3     3 
    6     6     7 
    6     7     9 
    9     2     3 
    9     7     3 

,sorted first by column 1, then column 2, and finally column 3.