Hello, thank you very much for replying. The code yields an error message
Error in strptime(x, format, tz = tz) : invalid 'x' argument But I can't see what's wrong with it, the Date/Time info is in the third column, format is "%Y-%m-%d %H:%M:%S". There is no time zone info in the data, could this be a problem ? Regards, Juliane Dr. Juliane Struve Daphne Jackson Fellow Imperial College London Department of Life Sciences Silwood Park Campus Buckhurst Road Ascot, Berkshire, SL5 7PY, UK Tel: +44 (0)20 7594 2527 Fax: +44 (0)1344 874 957 http://www.aquaticresources.org ________________________________________ From: Gabor Grothendieck [ggrothendi...@gmail.com] Sent: 27 September 2010 15:23 To: Struve, Juliane Cc: r-help@r-project.org Subject: Re: [R] plotting multiple animal tracks against Date/Time On Mon, Sep 27, 2010 at 10:01 AM, Struve, Juliane <j.str...@imperial.ac.uk> wrote: > Hi, > > I am sorry that my question wasn not very clearly formulated. My real data > comes in 47 .csv files, one for each of 47 individual, for example: > > "","Fish_ID","Date","R2sqrt" > "1",1646,2006-08-18 08:48:59,0 > "2",1646,2006-08-18 09:53:20,100 > > I would like to read the data for all individuals in the for loop below and > then combine them in a zoo object in order to plot them together. My > question is : How do I need to set up the for loop to deal with several > individuals ? I have put question marks the bits that I am missing. > > I very much appreciate your help. > > Regards, > > Juliane > > > ReleaseDates <- read.csv(file="ReleaseDates",head=TRUE,sep=",") > #reads in the individuals and their release dates > > for (i in 1:length(ReleaseDates)){ > Fish_ID <- ReleaseDates$Fish_ID[i] > ??? <- > read.zoo(file=paste("Results",Fish_ID,sep="_"),index.column=3,header=TRUE,FUN=as.chron,sep=",") > #reads in data for each in Fish_ID > } > z <- na.approx(cbind(???), na.rm = FALSE) > plot(z) > Try this (untested): library(zoo) filenames <- paste("Results", ReleaseDates$Fish_ID, sep = "_") # list of zoo objects removing 1st two columns in each file Lz <- lapply(filenames, read.zoo, header = TRUE, FUN = as.chron, sep = ",", colClasses = c("NULL", "NULL", "character", "numeric")) z <- do.call("merge", Lz) colnames(z) <- as.character(ReleaseDates$Fish_ID) # plot in single panel plot(na.approx(z), screen = 1) -- Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.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.
