MATLAB: How to detect the third saturday of each month

dates datenum day

Hello everyone! I have the follow vector of date-number:

734321 734328 734336 734342 734349 734356 734363 734371 734377 734384 734391 734399 734405 734412 734419 734427 734433 734440 734447 734454 734462 734468 734475 734482 734490 734495 734503 734510 734517 734525 734531 734538 734545

I need to remove from the array each dates (numbers) who aren't the third saturday of the month. How can I do? Many thanks!

Best Answer

d = [734321 734328 734336 734342 734349 734356 734363 734371 734377 ...
     734384 734391 734399 734405 734412 734419 734427 734433 734440 ...
     734447 734454 734462 734468 734475 734482 734490 734495 734503 ...
     734510 734517 734525 734531 734538 734545];
dSaturday = d(weekday(d) == 7);  % Saturdays only
dv        = datevec(dSaturday);
dThird    = d(dv(:, 3) >= 15 & dv(:, 3) <= 21);

Related Solutions

MATLAB: Find the Monday preceding the third Friday of the month

If you have the Financial Toolbox, you can do this with nweekdate which will do both aspects, finding third Friday, and finding the Monday in the same week as the third Friday.

Without Financial Tbx, this can be done with some grouping. Here is an example for 2015:

% 2015
Time = (datetime(2015,1,1):days(1):datetime(2015,12,31)).';
% Day of Month and whether it's a Friday
mt = month(Time);
idxFriday = strcmp(day(Time,'shortname'),'Fri');
% One to number of days
oneToN = (1:numel(Time))';
% Group Fridays by month
Fridays = accumarray(mt(idxFriday),oneToN(idxFriday),[],@(x){sort(x)});
% Keep third index and subtract four days for Monday
idxMonday = cellfun(@(x)x(3),Fridays)-4;
% Extract from Time
Time(idxTime)

Yields:

   12-Jan-2015
   16-Feb-2015
   16-Mar-2015
   13-Apr-2015
   11-May-2015
   15-Jun-2015
   13-Jul-2015
   17-Aug-2015
   14-Sep-2015
   12-Oct-2015
   16-Nov-2015
   14-Dec-2015

MATLAB: How to easily get for each day in 2013 the type of day? ( Weekday, Saturday, Sunday)

Hint:

    >> day_of_year = 1;
    >> [ num, str ]= weekday( datenum( 2013, 1, 1 ) + day_of_year - 1 )
    num =
         3
    str =
    Tue

and vectorized

    >> [ num, str ] = weekday( datenum( 2013, 1, 1 ) + [1:365] - 1 );
    >> num(1:7)
    ans =
         3     4     5     6     7     1     2

With Matlab Sun is weekday 1.

    >> str(1:3,:)
    ans =
    Tue
    Wed
    Thu
    >>

And finally inspired by Sean

    [ num, str ]= weekday( datenum( 2013, 1, 1 ) : datenum( 2013, 12, 31 ) );

Best Answer

Related Solutions

MATLAB: Find the Monday preceding the third Friday of the month

MATLAB: How to easily get for each day in 2013 the type of day? ( Weekday, Saturday, Sunday)

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