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

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JFz 2018-7-27

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评论： JFz 2018-8-3

采纳的回答： Stephen23

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!

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JFz 2018-7-27

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

JFz 2018-7-27

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

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Stephen23 2018-7-27

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

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Stephen23 2018-7-27

编辑：Stephen23 2018-7-27

"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 2018-7-30

This works. Thank you!

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Peter Perkins 2018-8-3

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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