transforming two date vectors

Dear all,

I have

A={

'2/11/2008'
  '30/11/08'
  '28/12/08'
  '25/01/09'
  '22/02/09'
  '22/03/09'
  '19/04/09'
  '17/05/09'
  '14/06/09'
  '12/7/2009'
  '9/8/2009'
  '6/9/2009'
  '4/10/2009'
  '1/11/2009'
  '29/11/09'
  '27/12/09'
  '31/01/10'
  '28/02/10'
  '28/03/10'
  '25/04/10'
  '23/05/10'
  '20/06/10'
  '18/07/10'
  '15/08/10'
  '12/9/2010'}

and

B={

 '1/4/2009'
  '2/1/2009'
  '3/1/2009'
  '4/5/2009'
  '5/3/2009'
  '5/31/2009'
  '7/5/2009'
  '8/2/2009'
  '8/30/2009'
  '10/4/2009'
  '11/1/2009'
  '11/29/2009'
  '1/3/2010'
  '1/31/2010'
  '2/28/2010'
  '4/4/2010'
  '5/2/2010'
  '5/30/2010'
  '7/4/2010'
  '8/1/2010'
  '8/29/2010'
  '10/3/2010'
  '10/31/2010'
  '11/28/2010'
  '1/2/2011'
  '1/30/2011'
  '2/27/2011'
  '4/3/2011'
  '5/1/2011'
  '5/29/2011'
  '7/3/2011'
  '7/31/2011'
  '8/28/2011'
  '10/2/2011'
  '10/30/2011'
  '11/27/2011'
  '1/4/2009'
  '2/1/2009'}

Sometimes I have either vector A or vector B. I want to find a unified code that will convert these vectors to the format dd/mm/yy irrespective of whether I have A or B

thanks

[Matt Fig]

Say one time you have

A = {'1/12/12';'2/10/2010'}

and another time you have

B = {'12/1/12';'10/2/2010'}

Can you tell me which of these is in dd/mm/ and which is in mm/dd/? If you can't tell, how is MATLAB supposed to tell?

[Sabbas]

B has a characteristic. you get dates of the format '10/31/2010' So you can have mm/dd/yyyy whereas in the first vector you do not have such cases. I suppose you can use this to "know" when you have vector A or vector B

thanks

[Matt Fig]

So you can guarantee that every set of dates will have at least one day D where D>12? You did not specify that in the original statement, but it is good to know!

Answer 1

[Andrei Bobrov]

a = regexp(DateInput,'(^\d*)(?=/)','match');
if any(str2double(cat(1,a{:}))>12)
    dfmt = 'dd/mm/yyyy';
else
    dfmt = 'mm/dd/yyyy';
end

Answer 2

[per isakson]

Try

   cac = cellfun( @(str) transpose( sscanf( str, '%d/%d/%*d' ) ) ...
                , A, 'uni', false ); 

   num = cell2mat( cac );
   isd = any( num >= 13, 1 );

   if all( not( isd ) )
       msg = 'Cannot decide';
   elseif all( isd )
       msg = 'Illegal date';
   elseif isd(1)
       msg = 'day first';
   elseif isd(2)
       msg = 'month first';
   else
       msg = 'Error in code';
   end

[per isakson]

To avoid the long line I edited and introduced an error, which is now fixed.