Assign Numeric Values to List of Strings

Hi,

If I have a cell array vertically sorted alphabetically as follows:

    X=['a';'a';'c';'h';'x';'x']

What code should I use to obtain the numeric output:

    Y=[1;1;2;3;4;4]

Where each integer in Y represents the alphabetic rank of the corresponding string in X.

Many thanks,

Cal

[per isakson]

Character array:

   X=['a';'a';'c';'h';'x';'x'];

Cell array:

    X={'a';'a';'c';'h';'x';'x'}

Answer 1

[Matt J]

[~,~,Y]=unique(X);

Answer 2

[Thorsten]

That's easy

 Y = [ 1 1 + cumsum(diff(X - 'a' + 1) > 0)'];

(and one of the reasons why I love Matlab :-))