How to sort data once it is read into matlab

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I am trying to sort the attached file first by column 1, then by column 3. I have tried the following code:
fid = fopen(filename);
data = textscan(fid, '%s %f %f');
fclose(fid);
matrix_data = [data{:}];
sort_data = sortrows(matrix_data, [1,3]);
This tells me that CAT arguments dimensions are not consistent.
Could someone tell me what is wrong with this code?
Thanks.

Accepted Answer

Cedric
Cedric on 18 Oct 2013
Edited: Cedric on 18 Oct 2013
The first column of data is a cell array of strings, whereas columns 2 and 3 are numeric arrays. You cannot concatenate them without performing first a conversion. You can also convert numeric arrays to cell arrays and have both strings and numbers in a large cell array. E.g.
matrix_data = [data{1}, num2cell(data{2}), num2cell(data{3})] ;
or
matrix_data = [data{1}, num2cell([data{2:3}])] ;
that you can then sort:
>> sort_data = sortrows(matrix_data, [1,3])
sort_data =
'A88888888888888888880011' [-65] [ 1]
'A88888888888888888880011' [-52] [ 2]
'A88888888888888888880011' [-64] [ 3]
'A88888888888888888880011' [-52] [ 4]
'A88888888888888888880011' [-57] [ 5]
'A88888888888888888880011' [-65] [ 6]
'A88888888888888888880011' [-57] [ 7]
'A88888888888888888880011' [-55] [ 8]
'A88888888888888888880012' [-66] [ 9]
'A88888888888888888880012' [-52] [10]
'A88888888888888888880012' [-68] [11]
'A88888888888888888880012' [-64] [12]
'A88888888888888888880012' [-44] [13]
'A88888888888888888880012' [-64] [14]
'A88888888888888888880012' [-40] [15]
'A88888888888888888880012' [-51] [16]
'A88888888888888888880013' [-55] [17]
'A88888888888888888880013' [-57] [18]
'A88888888888888888880013' [-49] [19]
'A88888888888888888880013' [-47] [20]
'A88888888888888888880013' [-64] [21]
'A88888888888888888880013' [-60] [22]
'A88888888888888888880013' [-67] [23]
'A88888888888888888880013' [-61] [24]

More Answers (1)

Vivek Selvam
Vivek Selvam on 18 Oct 2013
This should solve your problem.
data = textscan(fid, '%s %s %s');
instead of
data = textscan(fid, '%s %f %f');
  1 Comment
Cedric
Cedric on 18 Oct 2013
Edited: Cedric on 18 Oct 2013
Careful if you are comparing numbers which can change sign though, as this is sorting strings only:
>> sortrows( {'-88'; '-8'; '9'} )
ans =
'-8'
'-88'
'9'

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