Matching based on working days

Hi,

I have a vector A of dates and I want to create a vectors of working days that are 1 day prior, 1 week prior and 4 week prior to vector A dates.

How can I do so?

[Rik]

What have you tried so far?

[Clay Swackhamer]

What kind of data type is your date vector? If this is text stored in a cell we might want to consider converting to a datetime object. Otherwise if it is already a datetime object then you could use some built in features for those objects. You could find out in your code by running

whos A

in the command window.

[Wesso]

My vector is serial matlab date numbers. I had excel dates and transferred them to matlab using x2mdate.

I tried

B=A-1;

C=A-4;

D=A-28

But some of the days were saturdays and sundays. I posted the question in order to produce them neatly. Otherwise,I will use a loop to say that if the date is Saturday use Friday date, if it is a Sunday use Monday...

Answer 1

[Rik]

You can use the weekday function. You can easily adapt the function below to apply specific shifts.

A=datenum({'2019-04-07','2019-04-08','2019-04-06'});

B=A-1;
C=A-4;
D=A-28;

B=move_to_workday(B);
C=move_to_workday(C);
D=move_to_workday(D);

function A=move_to_workday(A)
%shift sat to fri, sun to mon, and leave the rest

% %option 1:
% isSunday=weekday(A)==1;
% isSaturday=weekday(A)==2;
% A(isSunday)=A(isSunday)+1;
% A(isSaturday)=A(isSaturday)-1;

%option 2:
shift=[1 0 0 0 0 0 -1];
%shift(weekday(A)) retains the shape of shift, instead of taking on the
%size of A, hence the reshape
A=A+reshape(shift(weekday(A)),size(A));
end

[Rik]

As a sidenote, the functions in this answer all support datetime inputs as well, despite the doc for weekday not mentioning this.

Answer 2

[Steven Lord]

If possible, switch to using datetime instead of serial date numbers. You can use the datetime options 'ConvertFrom', 'excel' or 'ConvertFrom', 'excel1904' to create the datetime array from the Microsoft Excel data.

If you use datetime you can use day (with the 'dayofweek' KIND input), isweekend, and/or dateshift.

D = datetime('today');
dayName = day(D, 'name')

dayCode = day(D, 'dayofweek')
isweekend(D) % As I write this it is Monday so this returns false

sundayBefore = dateshift(D, 'start', 'week')
isweekend(sundayBefore) % This returns true

If you want to go further with your classification of working days than just "weekday or weekend", the holidays function in Financial Toolbox accepts datetime as inputs.

[Wesso]

thanks for the tip