Question

I want to delete the repeat data in the flowing. Then ascending order according to the first column. Could you show the detail code to solve this problem? thank you very much.

  15.0    0.8     1.6    -0.0    -0.3  
  16.0    2.4    -0.2     0.1    -0.1  
  17.0    2.6    -0.6     0.2     0.2
  18.0    4.6     1.0     0.3     0.1
  19.0    2.3     1.4     0.9     0.2
  20.0    2.4     0.9     0.5     0.4


   6.0    5.8     2.5    -1.8    -1.9
   7.0    4.1     4.1    -0.8     1.6
   8.0    2.8     2.3     2.2    -0.5
   9.0   -1.5    -1.9     1.1     0.9
  10.0    0.9     0.2     0.0     0.1  

   9.0   -1.5    -1.9     1.1     0.9
  10.0    0.9     0.2     0.0     0.1
  11.0    2.3    -3.6     0.7    -0.6
  12.0   -1.2    -0.4    -0.2    -0.1
  13.0   -4.4     0.3    -0.3    -0.2
  14.0   -0.9     0.9    -0.4    -0.4
  15.0    0.8     1.6    -0.0    -0.3

Answer 1

From the documentation of unique, we find that the unique(B, 'rows') command will

• output unique rows only
• sort the output

So:

B = [...
    your data here
];

C = unique(B, 'rows');

will solve both your problems: the default for sort is to sort down the first column.