How do I sort an array according to the first column?

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Hi,
I have a cell array which I would like to sort according to the first column. But when I try using
high_emp_sort = sort(high_empathy_ID_factors);
% or
high_emp_sort = sortrows(high_empathy_ID_factors);
... then I only get back errors. Could somebody kindly help?
Jeff

Accepted Answer

Image Analyst
Image Analyst on 28 Jul 2022
Edited: Image Analyst on 28 Jul 2022
Did you mean by the first numerical column? Like this:
%====================================================================================
% Read in data.
storedStructure = load('high_empathy_ID_factors.mat');
ca = storedStructure.high_empathy_ID_factors;
data = cell2mat(ca(:, 2:end))
data = 17×4
18 12 14 16 17 19 15 11 8 18 14 22 25 11 17 7 16 22 9 5 11 13 14 10 13 23 16 19 10 18 17 25 9 14 14 15 15 18 17 10
fprintf('Read %d rows by %d columns into data.\n', size(data, 1), size(data, 2));
Read 17 rows by 4 columns into data.
%====================================================================================
% Sort by column 1.
fprintf('Sorting data by column 1.\n');
Sorting data by column 1.
[sortedData, sortOrder] = sortrows(data, 1);
%====================================================================================
% Sort original cell array also.
fprintf('Sorting original cell array in the same order of rows.\n');
Sorting original cell array in the same order of rows.
ca = ca(sortOrder, :)
ca = 17×5 cell array
{["61728b3e4e680d6c607f514c"]} {[ 8]} {[18]} {[14]} {[22]} {["5d4a41890e604c00011ade8b"]} {[ 9]} {[14]} {[14]} {[15]} {["5dc4bc30569be3387eb6b52f"]} {[10]} {[18]} {[17]} {[25]} {["5f5e7de4c81d3672642cd612"]} {[10]} {[25]} {[15]} {[21]} {["6134c80f7eab0971588b3d3a"]} {[11]} {[13]} {[14]} {[10]} {["5fb6ed2116919c000a99249e"]} {[13]} {[23]} {[16]} {[19]} {["5b59a51fca6d01000157a8c3"]} {[14]} {[ 2]} {[17]} {[11]} {["611b1d3794ac948af7e57e7a"]} {[15]} {[18]} {[17]} {[10]} {["5fd7782dee03dc08d3f3f491"]} {[15]} {[18]} {[16]} {[ 1]} {["5ecbb2347a5125043b1d3588"]} {[15]} {[26]} {[17]} {[13]} {["6155c449ebffeae654abd854"]} {[16]} {[22]} {[ 9]} {[ 5]} {["5eac84ff4efbe80ffd3962f1"]} {[16]} {[13]} {[18]} {[ 6]} {["5f5503435d41a489068ff50b"]} {[17]} {[19]} {[15]} {[11]} {["61520b079436973e05f72d33"]} {[18]} {[12]} {[14]} {[16]} {["5e92f01a49a5ba62bd0d5693"]} {[18]} {[15]} {[14]} {[ 7]} {["607ed750ad800928b1861317"]} {[19]} {[18]} {[14]} {[15]}
Or did you really mean by the long alphanumeric hexadecimal strings in the first column? Like this:
%====================================================================================
% Read in data.
storedStructure = load('high_empathy_ID_factors.mat')
storedStructure = struct with fields:
high_empathy_ID_factors: {17×5 cell}
ca = storedStructure.high_empathy_ID_factors;
data = cell2mat(ca(:, 2:end))
data = 17×4
18 12 14 16 17 19 15 11 8 18 14 22 25 11 17 7 16 22 9 5 11 13 14 10 13 23 16 19 10 18 17 25 9 14 14 15 15 18 17 10
[rows, columns] = size(data);
fprintf('Read %d rows by %d columns into data.\n', rows, columns);
Read 17 rows by 4 columns into data.
%====================================================================================
% Convert hex numbers in column 1 to decimal
for row = 1 : rows
c = char(ca{row, 1});
% Can only convert the first 16 digits.
numbers(row) = hex2dec(c(1:16));
end
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
Warning: Hexadecimal numbers representing integers greater than or equal to flintmax might not be represented exactly as double-precision floating-point values.
%====================================================================================
% Sort by column 1.
fprintf('Sorting data by column 1.\n');
Sorting data by column 1.
[sortedData, sortOrder] = sort(numbers)
sortedData = 1×17
1.0e+18 * 6.5825 6.7223 6.7567 6.8148 6.8220 6.8307 6.8694 6.8721 6.8970 6.9061 6.9532 6.9972 7.0044 7.0118 7.0127 7.0137 7.0218
sortOrder = 1×17
12 9 8 14 13 16 2 15 7 11 17 10 6 4 1 5 3
%====================================================================================
% Sort original cell array also.
fprintf('Sorting original cell array in the same order of rows.\n');
Sorting original cell array in the same order of rows.
ca = ca(sortOrder, :)
ca = 17×5 cell array
{["5b59a51fca6d01000157a8c3"]} {[14]} {[ 2]} {[17]} {[11]} {["5d4a41890e604c00011ade8b"]} {[ 9]} {[14]} {[14]} {[15]} {["5dc4bc30569be3387eb6b52f"]} {[10]} {[18]} {[17]} {[25]} {["5e92f01a49a5ba62bd0d5693"]} {[18]} {[15]} {[14]} {[ 7]} {["5eac84ff4efbe80ffd3962f1"]} {[16]} {[13]} {[18]} {[ 6]} {["5ecbb2347a5125043b1d3588"]} {[15]} {[26]} {[17]} {[13]} {["5f5503435d41a489068ff50b"]} {[17]} {[19]} {[15]} {[11]} {["5f5e7de4c81d3672642cd612"]} {[10]} {[25]} {[15]} {[21]} {["5fb6ed2116919c000a99249e"]} {[13]} {[23]} {[16]} {[19]} {["5fd7782dee03dc08d3f3f491"]} {[15]} {[18]} {[16]} {[ 1]} {["607ed750ad800928b1861317"]} {[19]} {[18]} {[14]} {[15]} {["611b1d3794ac948af7e57e7a"]} {[15]} {[18]} {[17]} {[10]} {["6134c80f7eab0971588b3d3a"]} {[11]} {[13]} {[14]} {[10]} {["614ec4f7be36eb900905644c"]} {[25]} {[11]} {[17]} {[ 7]} {["61520b079436973e05f72d33"]} {[18]} {[12]} {[14]} {[16]} {["6155c449ebffeae654abd854"]} {[16]} {[22]} {[ 9]} {[ 5]}
  3 Comments
lil brain
lil brain on 28 Jul 2022
The join() function actually worked really well. So I used that as it was the simplest approach thanks!

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