sort( ) do not work (or?)

Hello, Got a strange problem with the sort( ) function (I tried with sortrows as well, - same problem exist)..

I just attached the result of two different data tests. In both tests, I show the not sorted data, and the sorted data.. Each number is taken from a 1x1 cell.

Why can it be, that it does not sort the second test?

Hope to hear from someone, thanks in advance.

-best

[James Tursa]

Please show us the code you are using.

Answer 1

[dpb]

Both are sorted, but as the quotes around the data show the data are stored as cell strings so it's in ASCII order, not numeric. Convert the cellstring array to numeric prior to sorting...

sort(str2num(char(x)))

or equivalent where x is the cell array.

The first looks ok because all are of the same order of magnitude between 0-1 while the latter change. If you note, they're sorted by the first character of the number in order first.

[Martin]

thank you for enlightenment !

[Stephen23]

You could also use my FEX submission natsort, which sorts strings while taking into account the values of any numbers inside the strings (i.e. it provides a natural-order string sort):

>> X = {'9.246556','16.869455','9.781987','17.742497','8.356578','11.972240','8.085880','11.425893'};
>> natsort(X,'\d+\.\d+')
ans =
  8.085880
  8.356578
  9.246556
  9.781987
  11.425893
  11.972240
  16.869455
  17.742497

Yes, those are strings in the output, not numerics!

[Martin]

thanks for more knowledge! This problem has puzzled me a lot, but now I finally understand it. And my code works as I want it to.