How to sort a table by two columns?

Hello,

I want to sort a table by two column. The table hast three columns in total, one of them is a string. It looks kindof like this:

T= [1 4 'a';
    3 2 'b';
    1 3 'c';
    1 1 'd';
    2 5 'e';
    3 3 'f';
    2 2 'g']
   

and I want it to look like this:

    T_new= [ 1 1 'd';
             1 3 'c';
             1 4 'a';
             2 2 'g';
             2 5 'e':
             3 2 'b';
             3 3 'f']

I tried using the Function:

        T=sortrows(T,[1 2]); 

but it only sorts the first column but not the second:

       T_false= [ 1 4 'a';
                  1 3 'c';
                  1 1 'd';
                  2 5 'e';
                  2 2 'g';
                  3 2 'b';
                  3 3 'f']

I think it's pry because of the third column being a string because I have been using this function befor with only numeric matrices and it worked fine.

I would be thankful for any tipps.

Thank you, Anja

Answer 1

[Kevin Chng]

I follow your solution, it sorts two columns for me.

See :

a = [1 3 1 1 2 3 2];
b = [4 2 3 1 5 3 2];
c = ['a' 'b' 'c' 'd' 'e' 'f' 'g'];
t=table(a',b',c');
t = sortrows(t,[1,2])

Result :

T =

  7×3 table

    Var1    Var2    Var3
    ____    ____    ____

     1       1       d  
     1       3       c  
     1       4       a  
     2       2       g  
     2       5       e  
     3       2       b  
     3       3       f  

[Anja Lauer]

If I try it with this small random table it works for me as well, but with my large one (the one I uploaded) it doesn't :/

[Kevin Chng]

Hi Anja,

Your updated one is correct, there are many unseen decimal point. try:

format long
load testtable.mat
H = sortrows(H,[1,2]);
%display the top 10, then you will understand
H(1:,10,:)

from the code above, you will understand since some decimal point is hidden.

Accept my answer if it answers your question.

[Anja Lauer]

I did not think about the hidden decimal points! Thank you so much! I know what to do now!