How do I read in a text file and sort it by a column

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I have a file which I am trying to read and then sort by column A and then by column C. The text file is attached and has 3 columns. This is what I have tried but it will not let me use the sort function after reading it in this way:
function data = ResultsScript(filename)
fid = fopen(filename);
data = textscan(fid, '%s %f %f');
fclose(fid);
end
Then I call this function and try to sort it using:
fileName = 'Example.txt';
A = ResultsScript(fileName);
sortrows(A,[1,3]);
Running this gives the following error message:
??? Index exceeds matrix dimensions.
Error in ==> sortrows>sort_cell_back_to_front at 133
ndx = ndx(ind);
Error in ==> sortrows at 90
ndx = sort_cell_back_to_front(x_sub, col);
Error in ==> GetResults at 3
sortrows(A,[1,3]);
Any help is greatly appreciated.

Accepted Answer

sixwwwwww
sixwwwwww on 12 Oct 2013
Dear Aaron, the problem here is that function "textscan" output data in the form of cell array which you must convert first into a matrix before using "sortrows" function because "sortrows" only accept vector or matrix data. So after converting it to proper form you can apply "sortrows". Also don't use "%s" to read values of double type instead use "%f" or better "%n". Following is the corrected code for this purpose:
fid = fopen(filename);
cell_data = textscan(fid, '%n %n %n');
fclose(fid);
matrix_data = [cell_data{:}];
After this you can apply:
sorted_data = sortrows(matrix_data, [1 3]);
  2 Comments
Aaron
Aaron on 12 Oct 2013
Thank you very much for you help! And the first column of data isn't actually a double, it is a hexadecimal number. An EPC from a RFID tag.
sixwwwwww
sixwwwwww on 12 Oct 2013
You are welcome and sorry for misunderstanding about EPC because I don't know about EPC.

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