Hi, use tableName[["columnName"]] without quotes, e.g. tableName[[columnName]] # see ?"[["
and indexing is done via x<-length(tableName[[columnName]][tableName[[columnName]] > 6] ) but you may consider x<-sum(tableName[[columnName]]>6) which saves some time and typing Hth. Am 27.07.2011 17:22, schrieb Lin, YunHui: > Hi all, > > I've been having trouble with something that seems like it should be > fairly straight forward. Any help at all from more experienced users is > appreciated! > > > > I'd like to write a function that uses a column name as an argument. > However, I run into problems when I try to reference this column within > the function. > > For example, > > > > findCutoff <- function(tableName, columnName) { > > > > temporaryTable <- subset(tableName, select = c(V1, V4, > columnName)) > > > > x <- length(tableName$columnName [tableName$columnName > > 6] ) > > > > ...etc. > > } > > > > I know a couple of ways to reference a column: > > 1. tableName$columnName > > 2. tableName[["columnName"]] > > I tried turning the function arguments into a string like > "tableName$columnName" to use within my function, but unfortunately that > didn't work. With the second method I run into problems if I want to > compute something like x in the example function above. > > > > Any ideas, suggestions to try? > > > > Thanks in advance for any responses! > > > > YunHui Lisa Lin > Intern, Customer Intelligence & Web Analytics > > Moody's Corporation > yunhui....@moodys.com <mailto:heather.andr...@moodys.com> > > > > > ----------------------------------------- > The information contained in this e-mail message, and any attachment thereto, > is confidential and may not be disclosed without our express permission. If > you are not the intended recipient or an employee or agent responsible for > delivering this message to the intended recipient, you are hereby notified > that you have received this message in error and that any review, > dissemination, distribution or copying of this message, or any attachment > thereto, in whole or in part, is strictly prohibited. If you have received > this message in error, please immediately notify us by telephone, fax or > e-mail and delete the message and all of its attachments. Thank you. Every > effort is made to keep our network free from viruses. You should, however, > review this e-mail message, as well as any attachment thereto, for viruses. > We take no responsibility and have no liability for any computer virus which > may be transferred via this e-mail message. > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. -- Eik Vettorazzi Institut für Medizinische Biometrie und Epidemiologie Universitätsklinikum Hamburg-Eppendorf Martinistr. 52 20246 Hamburg T ++49/40/7410-58243 F ++49/40/7410-57790 ______________________________________________ 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.