> -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-bounces@r- > project.org] On Behalf Of Rich Shepard > Sent: Thursday, October 27, 2011 11:17 AM > To: r-help@r-project.org > Subject: Re: [R] Syntax Check: rshape2 melt() > > On Thu, 27 Oct 2011, Nordlund, Dan (DSHS/RDA) wrote: > > > You should be able to get what you want using the dcast function (I > think). > > > > test.melted <- melt(tds.anal) > > dcast(test.melted, site + sampdate ~ param) > > Dan, > > I don't think the data frame melted properly. I tried the dcast() > but > sampdate is not found: > > c.tds.anal <- dcast(m.tds.anal, site + sampdate ~ param) > Error in eval(expr, envir, enclos) : object 'sampdate' not found > > Perhaps I still need to better understand the parameters in the > melt() > function. > > Rich >
Rich, I read in the sample data that you put in an earlier post. > tds.anal <- read.table('clipboard',header=TRUE) > tds.anal site sampdate param quant 1 UDS-O 2006-12-06 TDS 10800 4 STC-FS 1996-06-14 Cond 280 7 UDS-O 2007-10-04 Mg 1620 9 UDS-O 2007-10-04 SO4 7580 19 JCM-10B 2007-06-21 Ca 79 20 JCM-10B 2007-06-21 Cl 114 Then ran the following code > library(reshape2) > melt(tds.anal) Using site, sampdate, param as id variables site sampdate param variable value 1 UDS-O 2006-12-06 TDS quant 10800 2 STC-FS 1996-06-14 Cond quant 280 3 UDS-O 2007-10-04 Mg quant 1620 4 UDS-O 2007-10-04 SO4 quant 7580 5 JCM-10B 2007-06-21 Ca quant 79 6 JCM-10B 2007-06-21 Cl quant 114 > dcast(melt(tds.anal), site + sampdate ~ param) Using site, sampdate, param as id variables site sampdate Ca Cl Cond Mg SO4 TDS 1 JCM-10B 2007-06-21 79 114 NA NA NA NA 2 STC-FS 1996-06-14 NA NA 280 NA NA NA 3 UDS-O 2006-12-06 NA NA NA NA NA 10800 4 UDS-O 2007-10-04 NA NA NA 1620 7580 NA > So you can see that at least it worked for me. Can you show us the actual output you get when running the melt and dcast functions on a sample of your data? I am not sure why sampdate is not found since it appears to be in your original sample data. Dan Daniel J. Nordlund Washington State Department of Social and Health Services Planning, Performance, and Accountability Research and Data Analysis Division Olympia, WA 98504-5204 ______________________________________________ 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.