MATLAB: Sort Matrix by rows

matrixmatrix arraysort

I have a matrix which first row indicates index numbers and second indicated the data. For example it goes like this:
1    2    3    4    5    6
23   45   10   90   11   34
I want to sort these descending but I don't want to loose the corresponding index either.
4    2    6    1    5    3
90   45   34   23   11   10
I have a large amount of data so it needs to be efficient too. How can I do that?

Best Answer

Hi,
A =
       1     2     3     4     5     6
      23    45    10    90    11    34
>> A=A'
A =
       1    23
       2    45
       3    10
       4    90
       5    11
       6    34
  >> B=sortrows(A,-2)
B =
       4    90
       2    45
       6    34
       1    23
       5    11
       3    10
>> B=B'
B =
       4     2     6     1     5     3
      90    45    34    23    11    10
Or short:
B=(sortrows(A',-2))'
B =
     4     2     6     1     5     3
    90    45    34    23    11    10
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