counting weekday in a month in R

-----Original Message-----
From: r-help-bounces at r-project.org 
[mailto:r-help-bounces at r-project.org] On Behalf Of tom soyer
Sent: Thursday, December 13, 2007 1:27 PM
To: r-help at r-project.org
Subject: [R] counting weekday in a month in R

Hi,

I am trying to count weekday of the month using R. For 
example, 1/4/2001
is the 4th weekday of Jan, and 1/5/2001 is the 5th weekday of 
the month, and
1/8/2001 is the 6th weekday of the month, etc. I get as far 
as extracting
the weekdays from a sequence of dates (see below). But I have not yet
figured out a fast way of counting without using a For Loop. 
Does anyone
know how to do such counting efficiently in R?

Thanks!

library(chron)
dts=seq(dates("1/4/01"),dates("3/31/01"),1)
wkday=dts[!is.weekend(dts)]
weekdays(wkday)
 [1] Thu Fri Mon Tue Wed Thu Fri Mon Tue Wed Thu Fri Mon Tue 
Wed Thu Fri Mon
Tue Wed
[21] Thu Fri Mon Tue Wed Thu Fri Mon Tue Wed Thu Fri Mon Tue 
Wed Thu Fri Mon
Tue Wed
[41] Thu Fri Mon Tue Wed Thu Fri Mon Tue Wed Thu Fri Mon Tue 
Wed Thu Fri Mon
Tue Wed
[61] Thu Fri
Levels: Sun < Mon < Tue < Wed < Thu < Fri < Sat



-- 
Tom