the problem you get comes from the fact that you attach the data.frame, e.g., it can be re-produced by:
x1 <- rnorm(30) dat <- data.frame(x1 = rnorm(30)) attach(dat) look at ?attach for more details; you could consider with() as an alternative. I hope it helps. Best, Dimitris -- Dimitris Rizopoulos Ph.D. Student Biostatistical Centre School of Public Health Catholic University of Leuven Address: Kapucijnenvoer 35, Leuven, Belgium Tel: +32/(0)16/336899 Fax: +32/(0)16/337015 Web: http://med.kuleuven.be/biostat/ http://www.student.kuleuven.be/~m0390867/dimitris.htm Quoting Ben Fairbank <[EMAIL PROTECTED]>: > I have several data frames, each with six variables and several > hundred > cases broken out from a larger dataframe by eleven values of a > factor > called "Division". I have to perform the same analysis on each one. > I > would like to do it by creating a data frame called data2 eleven > times, > once with data corresponding to each value of the factor, and > performing > the same analysis on each of the eleven values of data2. However, > when > I assign to data2 the value of one of my data frames, e.g. data2 <- > Florida, and then attach data2, I get the warning > > > > The following object(s) are masked from data2 ( position 3 ) > : > > Day Division SchedNo Spent TimeEnter TimeInStr > > The following object(s) are masked from Alb3 : > > Day Division SchedNo Spent TimeEnter TimeInStr > > The following object(s) are masked from data2 ( position 5 ) > : > > Day Division SchedNo Spent TimeEnter TimeInStr > > > > I am having trouble finding an explanation of these messages, what > the > "position" refers to, and what it means to be "masked." Can someone > steer me to an online explanation? > > > > And by the way, one of the analyses I have to perform is simply to > tabulate the days of the week that occur in variable "Day" by using > table(Day) which gives, for example, > > > > Day > > Fri Mon Sat Sun Thur Tue Wed > > 173 191 111 92 188 218 187 > > > > What is the proper syntax for doing that by levels of a factor > within > the large data frame containing all eleven factors? I have > unsuccessfully tried to use "by". > > > > Thanks, > > > > Ben F. > > > [[alternative HTML version deleted]] > > ______________________________________________ > [email protected] mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! > http://www.R-project.org/posting-guide.html > > Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
