ABAP Function module for BW

Question

Hello Gurus,
I am not an ABAPer, I work in BW module.
I have a requirement to write a routine which will check the following logic
In BW, I have a field called Posting Date (0PSTNG_DATE). This field is currently set to sy-datum. But i need to write a routine which will find last friday's date and update this field with friday's date.
Eg: If sy-datum = 03/09/2007 then i need to populate posting date field as 31/08/2007.
Sy-datum can be any day of the week. But it should always write last week friday's date.
Is there any standard function module which i can use here.
Thanks in advance.
Cheers
POPS

Answer 1

Hi,
  call function 'DAY_ATTRIBUTES_GET'
       exporting
            date_from                  = sy-datum
            date_to                    = sy-datum
            language                   = sy-langu
       tables
            day_attributes             = i_day
       exceptions
            factory_calendar_not_found = 01
            holiday_calendar_not_found = 02
            date_has_invalid_format    = 03
            date_inconsistency         = 04.
if i_day-weekday > 5.
   v_friday = sy-datum - ( i_day-weekday - 5 ).
endif.
if i_day-weekday < 5.
   v_friday = sy-datum - ( i_day-weekday + 2 ) .
endif.
if i_day-weekday = 5.
   v_friday = sy-datum.
endif.
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