I'm trying to read in a file using the function fread.
The file that I'm trying to read in has about 100 lines of information I
don't want prior to getting to my matrix of data that I do want. On the
line prior to the data I want there is always a string identifier
"*end*"
The following fread call:
impcoord <-
fread('H:/SBE19plus_01907535_2015_06_17_0093.cnv',skip="*END*")
almost gets me there but it starts reading AT *END* and I'd like to have it
start the line after. I can't figure out how to make this work.
I know I could have a two step function where I have a function scan the
file to Identify the line that has *END* but I thought I could just do it
with one fread() call.
thanks for the help.
Trevor
[[alternative HTML version deleted]]
Hi Trevor,
I couldn't work out how to do it with just fread, but perhaps this will
help:
# create a test file
sink("test_fread.dat")
cat("This is the header of a file\n")
cat("that ends with the word *end*\n")
cat("Col1 Col2\n1 2\n3 4\n5 6\n")
sink()
# try to read it
test_con<-file("test_fread.dat","rt")
header_lines<-1
while(header_lines) {
nextline<-readLines(test_con,1)
header_lines<-length(grep("*end",nextline,fixed=TRUE))==0
}
fread_dat<-read.table(test_con,header=TRUE)
Jim
On Sat, Jun 27, 2015 at 2:16 AM, Trevor Davies <davies.trevor at
gmail.com> wrote:> I'm trying to read in a file using the function fread.
>
> The file that I'm trying to read in has about 100 lines of information
I
> don't want prior to getting to my matrix of data that I do want. On
the
> line prior to the data I want there is always a string identifier
"*end*"
>
> The following fread call:
>
> impcoord <-
fread('H:/SBE19plus_01907535_2015_06_17_0093.cnv',skip="*END*")
>
> almost gets me there but it starts reading AT *END* and I'd like to
have it
> start the line after. I can't figure out how to make this work.
>
> I know I could have a two step function where I have a function scan the
> file to Identify the line that has *END* but I thought I could just do it
> with one fread() call.
>
> thanks for the help.
> Trevor
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.
Hi Jim,
Thanks,Jim. I couldn't get fread to work either for this.
I ended up with this:
txt<- readLines('test_fread.dat');
data.frame1 <- read.table(text=txt, sep='', header=FALSE,
skip=grep('*END*', txt))
BTW, i use that Map Rose function you wrote a few years back quite often.
Thanks for the contributions!
Trevor
On Sun, Jun 28, 2015 at 2:21 AM, Jim Lemon <drjimlemon at gmail.com>
wrote:
> Hi Trevor,
> I couldn't work out how to do it with just fread, but perhaps this will
> help:
>
> # create a test file
> sink("test_fread.dat")
> cat("This is the header of a file\n")
> cat("that ends with the word *end*\n")
> cat("Col1 Col2\n1 2\n3 4\n5 6\n")
> sink()
> # try to read it
> test_con<-file("test_fread.dat","rt")
> header_lines<-1
> while(header_lines) {
> nextline<-readLines(test_con,1)
> header_lines<-length(grep("*end",nextline,fixed=TRUE))==0
> }
> fread_dat<-read.table(test_con,header=TRUE)
>
> Jim
>
> On Sat, Jun 27, 2015 at 2:16 AM, Trevor Davies <davies.trevor at
gmail.com>
> wrote:
> > I'm trying to read in a file using the function fread.
> >
> > The file that I'm trying to read in has about 100 lines of
information I
> > don't want prior to getting to my matrix of data that I do want.
On the
> > line prior to the data I want there is always a string identifier
"*end*"
> >
> > The following fread call:
> >
> > impcoord <-
>
fread('H:/SBE19plus_01907535_2015_06_17_0093.cnv',skip="*END*")
> >
> > almost gets me there but it starts reading AT *END* and I'd like
to have
> it
> > start the line after. I can't figure out how to make this work.
> >
> > I know I could have a two step function where I have a function scan
the
> > file to Identify the line that has *END* but I thought I could just do
it
> > with one fread() call.
> >
> > thanks for the help.
> > Trevor
> >
> > [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> > 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.
>
[[alternative HTML version deleted]]