Table back to its original form?

So one can sort the data in any column of a table in an ascending / descending order from the drop-down list on the heading. However, is there a way to turn the sorted table back to its original form (unsorted)?

Answer 1

[Star Strider]

If you kept the index vector from the sorted data, you can ‘unsort’ them:

x = randi(99, 10, 1);                       % Original Data
[xs,idx] = sort(x);                         % Sorted Data & Index
x_unsort(idx) = xs;                         % ‘Unsorted’ Data

If you didn’t keep it, all hope is lost.

[Guillaume]

If you didn’t keep it, all hope is lost

Which is exactly the case (didn't keep it) if you use the UI to do the sorting. You'll notice that matlab outputs the command it uses to do the sorting to the command window, and it is of the form:

yourtable = sortrows(yourtable, columnname, direction);

whereas you'd need

[yourtable, order] = sortrows(...)

to be able to restore the order.

There's no workaround other than doing the sorting through the command window rather than the UI, unfortunately.

Answer 2

[KSSV]

Read about Sort. You have to do that using a command/ function sort.

k = [3 4 5 1 2 3 6] ;
[val,idx] = sort(k) ;

Your sorted k is val and your original data remains same as k.

[wesleynotwise]

Thanks, but I would like to know how to 'undo' the sorted table in Matlab.

[Peter Perkins]

If by "in MATLAB", you mean "at the MATLAB command line", others have provided the answer: use the second output of sort. If you mean "in the Variable Editor", can you not use the Undo button or ctrl-z?

[breathi]

@Peter Perkins: You can use Ctrl+Z or the Undo button, but only once. Once you make 2 sort commands in the Variable Editor, it's over.