Remove leading zeros from dates strings

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I need to find the number of times a set of dates is included in a large text file. The problem is that the text file does not use leading zeros for months and days.
My code should look something like this:
for it=1:10
numberOfTimes(it)=size(regexp(myText, datestr(dayOne+days(it), 'mm/dd/yy')), 2);
  1 Comment
jonas on 16 Jul 2020
Edited: jonas on 16 Jul 2020
Why not simply count the dates with hist?

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Accepted Answer

jonas on 16 Jul 2020
You can use histogram() to count occurences, either with datetime or categoricals as input.
dates = datetime(2010,1,12) + rand(1000,1)*days(365);
% with categoricals
dates_cell = cellstr(datestr(dates,'mm/dd/yy'));
dates_cat = categorical(dates_cell);
H = histogram(dates_cat)
Walter Roberson
Walter Roberson on 17 Jul 2020
You could use mm and then use regexp to strip out leading 0. But it hardly seems worth it considering that datetime() can handle the situation
dates = datetime(2010,1,12) + rand(10,1)*days(365);
dates.Format = 'M/d/yy';
dates_cat = categorical(cellstr(dates));

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More Answers (1)

Steven Lord
Steven Lord on 16 Jul 2020
Use M instead of MM and d instead of dd in the input format. According to the description of the Format property on the documentation page (which is referenced in the documentation for 'InputFormat'), M handles "Month, numerical using one or two digits" as opposed to MM which handles "Month, numerical using two digits".
>> datetime('07-16-2020', 'InputFormat', 'M-dd-yyyy')
ans =
>> datetime('7-16-2020', 'InputFormat', 'M-dd-yyyy')
ans =
  1 Comment
Santiago Costantino
Santiago Costantino on 16 Jul 2020
Edited: Santiago Costantino on 16 Jul 2020
Sorry, I guess my question was not clear enough.
The dates in the text file are written as '4/7/20' for April 7th 2020. I need to find the number of occurrences of each one of many different and consecutive dates in the text.

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