Thanks, that's helpful because I can see the individuals and how many times they accessed:
The 'plyr' solution of Karl Ove Hufthammer gives me the exact summary statistics that I'm looking for.
 
Jab

--- On Fri, 13/11/09, markleeds@verizon.net <markleeds@verizon.net> wrote:


From: markleeds@verizon.net <markleeds@verizon.net>
Subject: Re: Re: [R] processing log file
To: jabezwuk@yahoo.co.uk
Date: Friday, 13 November, 2009, 16:36


Hi: I think below does what you want but it doesn't come out formatted very nicely. Maybe someone can show you
the formatting ? Good luck.

table.users <- read.table(textConnection("Date UserName Machine
2008-11-25     John     641
2008-11-25    Clive     611
2008-11-25   Jeremy     641
2008-11-25     Walt     722
2008-11-25     Tony     645
2008-11-26     Tony     645
2008-11-26     Tony     641
2008-11-26     Tony     641
2008-11-26     Walt     641
2008-11-26     Walt     645
2008-11-30     John     641
2008-11-30    Clive     611
2008-11-30     Tony     641
2008-11-30     John     641
2008-11-30     John     641"),header=TRUE,as.is=TRUE)

print(table.users)
print(str(table.users))

lapply(split(table.users,table.users$Date),function(.df) {
    table(.df$Machine)
})

lapply(split(table.users,table.users$Date),function(.df) {
    table(.df$UserName)
})






On Nov 13, 2009, Karl Ove Hufthammer <karl@huftis.org> wrote: 

On Fri, 13 Nov 2009 11:03:31 +0000 (GMT) Jabez Wilson 
<jabezwuk@yahoo.co.uk> wrote:
> What I want to do is to find out how many unique users logged 
> on each day, and how many individual machines where accessed per day.

Use the 'plyr' package:

library(plyr)
ddply(table.users, .(Date), summarise,
users=length(unique(Username)),
machines=length(unique(Machine)))

-- 
Karl Ove Hufthammer

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.



      
	[[alternative HTML version deleted]]


