On Wed, Jun 22, 2011 at 5:45 PM, Changbin Du <changb...@gmail.com> wrote: > HI, Dear R community, > > I have a large data set names dd.txt, the columns are: there are 2402 > variables. > > a1, b1, ..z1, a11, b11, ...z11, a111, b111, ..z111.. > > IF I dont know the relative position of the columns, but I know I need the > following variables: > var<-c(a1, c1,a11,b11,f111) > > Can I use read.columns to read the data into R? > > I have tried the following codes, but it does not work > > hh<-read.columns("/house/homedirs/c/cdu/operon/gh/dd.dimer", > required.col=NULL, text.to.search=var, sep="\t", skip=0, quote="", fill=T) >
Depending on the precise format of the input you might be able to use read.csv.sql in sqldf. (You may need to modify the args a bit relative to what is shown below but the basic idea is hopefully clear.) See ?read.csv.sql and also the examples on the sqldf home page (http://sqldf.googlecode.com) for more info. library(sqldf) DF <- read.csv.sql("myfile", header = FALSE, sep = "\t", sql = "select a1,c1,a11,b11,f111 from file") -- 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.