>Hi everybody,
>
>Given 52 weeks in a year and week definition (from Sat through Friday) I need to calculate Week's first day, week's last day and some other dates for the given year for each week. What would be a formula here?
>
>Thanks a lot in advance.

This returns the first Saturday of a given year. From there, you can add a multiple of 7 to get to any other given Saturday.

IOW, the 5th week begins on:

? firstSaturday(2001) + (5-1)*7  && depends on how you treat the days b4 the
                                 && first Saturday

procedure firstSaturday
lparameters lnYear
	return date(lnYear, 1, 1) + (7 - dow(date(lnYear, 1, 1)))
endproc