How to extract Jan and feb dates from an array of date strings?

Hi,

I have an array of cells of date string. I need to extract all the dates in Jan and Feb. How to do that? Thanks a lot!

[Stephen23]

@JFz: what date format do the strings use? Please upload the cell array in a .mat file, by clicking the paperclip button.

[JFz]

The format in each sell is: 'mm/dd/yyyy'. some like: '1/1/2018' '2/1/2018' .... Thanks!

[JFz]

Something I created with {'1/1/2018'; '2/1/2018'; ...}

Answer 1

[Stephen23]

>> C = {'1/1/2018'; '2/1/2018'; '12/31/2018'};
>> X = cellfun('isempty',regexp(C,'^[12]/','once'));
>> D = C(~X)

[JFz]

Thanks. But what if I have C = {'1/1/2018'; '2/1/2018'; '3/1/2018'; '4/1/2018'; '5/1/2018';'12/31/2018'}; And I would like to extract 1/2/2018 and 2/1/2018?

[Stephen23]

"C = {'1/1/2018'; '2/1/2018'; '3/1/2018'; '4/1/2018'; '5/1/2018';'12/31/2018'}; And I would like to extract 1/2/2018 and 2/1/2018?"

Your example cell array does not contain '1/2/2018', should that example output actually be '1/1/2018' (which does exist in C) ? In which case my code already does that:

>> C = {'1/1/2018'; '2/1/2018'; '3/1/2018'; '4/1/2018'; '5/1/2018';'12/31/2018'};
>> X = cellfun('isempty',regexp(C,'^[12]/','once'));
>> D = C(~X)
D = 
    '1/1/2018'
    '2/1/2018'

[JFz]

This works. Thank you!

Answer 2

[Peter Perkins]

If possible, don't do this with text. Convert to datetimes:

>> d = datetime(2018,randi(6,10,1),1)
d = 
  10×1 datetime array
   01-Jan-2018
   01-Mar-2018
   01-Jan-2018
   01-Mar-2018
   01-Jan-2018
   01-May-2018
   01-Mar-2018
   01-Jan-2018
   01-Feb-2018
   01-Mar-2018
>> d(d.Month==1 | d.Month==2)
ans = 
  5×1 datetime array
   01-Jan-2018
   01-Jan-2018
   01-Jan-2018
   01-Jan-2018
   01-Feb-2018

[JFz]

Thank you!