detecting the existence of alphabetical elements

Dear all, I would like to detect whether a string contains an alphabetical letter. A simple way of solving this problem is writing a function such as. But is there any better, more concise and faster way? Can one use, say, regular expressions and if so how?

thanks, Pat.

 function flag=detect_alphabet(mystring)
 referenceSet={'a','b','c','d',...,'z'};
 flag=false;
 for ii=1:length(mystring)
    if ismember(mystring(ii),referenceSet)
        flag=true;
        break
    end
 end

Answer 1

[Matt Fig]

Perhaps best of all:

str = 'adsf2342adsfwerreoj9f3f';
str2 = '23423';
flag = any(isletter(str))
flag = any(isletter(str2))

Answer 2

[Oleg Komarov]

regexpr(str,'[a-zA-Z]')

Answer 3

[Matt Fig]

str = 'adsf2342adsfwerreoj9f3f';
str2 = '23423';
flag = ~isempty(regexp(str,'[A-Za-z]'))
flag = ~isempty(regexp(str2,'[A-Za-z]'))

Answer 4

[Jan]

flag = any(ismember(mystring, 'a':'z'))

But now I'm lost in the incompatibilities of Matlab versions. Perhaps it must now be:

flag = any(ismember(mystring, char('a':'z')))

Alternatively:

flag = any(mystring >= 'a' & mystring <= 'z')

Or:

flag = any(isstrprop(mystring, 'lower'))

In all cases a loop is not required.

[Matt Fig]

flag = any((str>='A' & str<='Z') | ((str>='a' & str<='z')))

Answer 5

[Patrick Mboma]

Dear all, thank you SO much for a prompt reply. I now have many suggestions but don't know which one is the best. I will test them all and see, which one works best.

[Image Analyst]

Well for what it's worth, I was going to answer isletter() until Matt beat me to it.