Peter's suggestion qdata[order(qdata$flow, decreasing=TRUE), ] would work if qdata were a data.frame, where the $column syntax picks out a column. You probably have a matrix so use [,"flow"] instead of $flow to extract the column called "flow". qdata[order(qdata[,"flow"], decreasing=TRUE), ] (Both syntaxes work for data.frames, but only the latter works for matrices.)
Showing the result of print(dataset) is not sufficient to show helpers what you have. Data.frames and matrices, both being 2 dimensional datasets, have a similar printouts. A printout that looks like 2010-03-10 might represent a Date object, a POSIXlt object, a single string, the level of a factor, an arithmetic expression, etc. The output of dput(dataset) will spell out those details and we can copy and paste it into an R session to recreate your dataset, as it exists in your R session. If dput's output is too big, trim your dataset down to something that still demonstrates the problem but will fit in the mail. If trimming it down makes the problem disappear, showing the output of str(dataset) would be helpful: it tells us about the dataset's structure but, unlike dput, it makes us think about how to recreate the object that gave you trouble. You can also show the commands used to make the the problematic dataset. Make sure they don't involve reading some file that is not on our computers. Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] On Behalf Of emwater > Sent: Wednesday, March 10, 2010 1:07 AM > To: r-help@r-project.org > Subject: Re: [R] sorting data whilst ignoring NA's > > > Thanks for these suggestions. I tried them out and I get the > error message: > Error in qdata$flow : $ operator is invalid for atomic vectors > > Can anyone offer further suggestions on how to extract the values from > atomic vectors? > > Thanks again > Emma > -- > View this message in context: > http://n4.nabble.com/sorting-data-whilst-ignoring-NA-s-tp15862 77p1587108.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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. > ______________________________________________ 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.
