[R] read.table

Weiwei Shi helprhelp at gmail.com
Wed Jul 13 23:52:05 CEST 2005


Sorry for last post. 
I don't know why i got the error message last time.
but if i did in the following way:
t<-scan('train1.dat',  sep='|', na.string='.')
t2<-matrix(t, nrow=195, ncol=273529)
t3<-t(t2)
t4<-as.data.frame(t3)

now I got what i needed.

Thanks a lot for Gabor's prompt help.

weiwei

On 7/13/05, Weiwei Shi <helprhelp at gmail.com> wrote:
> i think what you meant is
> > trn<-matrix(scan('train1.dat',  sep='|', na.string='.'), nrow=195, ncol=273529)
> and then transpose it. However:
>     Error: cannot allocate vector of size 512000 Kb
> 
> the answer is no :(
> 
> I think i am going to write my own function to split the result from
> scan but not sure if it can be made into matrix or not even if I
> succeed.
> 
> 
> On 7/13/05, Gabor Grothendieck <ggrothendieck at gmail.com> wrote:
> > Try reading it into and transposing the matrix afterwards.  Don't know if
> > that would work but its worth a try.  Actually if you
> > are having problems read it into a vector, check that its of the required
> > size, just in case, and then turn it into a matrix and transpose it.
> >
> >
> > On 7/13/05, Weiwei Shi <helprhelp at gmail.com> wrote:
> > > there is another problem since last time i forgot "byrow" :(
> > > > trn<-matrix(scan('train1.dat',  sep='|', na.string='.'), nrow=273529, ncol=195, byrow=T)
> > > Read 53338155 items
> > > Error: cannot allocate vector of size 416704 Kb
> > >
> > > please help with this 'simple' reading task.
> > >
> > > weiwei
> > >
> > > On 7/13/05, Weiwei Shi <helprhelp at gmail.com> wrote:
> > > > that sort of works for my purpose.
> > > >
> > > > btw, is there a bettter way to get data.frame by passing around
> > > > matrix(). Since I could not find data.frame() with nrow or ncol
> > > > arguments. so i have to use matrix first and then as.data.frame to
> > > > convert it.
> > > >
> > > > is there any other (better) way?
> > > >
> > > > weiwei
> > > >
> > > > On 7/13/05, Gabor Grothendieck <ggrothendieck at gmail.com> wrote:
> > > > >
> > > > > You could use the nlines= argument to scan to read in a
> > > > > portion at a time.
> > > > >
> > > > >
> > > > >
> > > > > On 7/13/05, Weiwei Shi <helprhelp at gmail.com> wrote:
> > > > > >
> > > > > > add:
> > > > > > I used
> > > > > > trn<-matrix(scan('train1.dat',  sep='|', na.string='.'), nrow=273529,
> > > > > ncol=195)
> > > > > >
> > > > > > it is done.
> > > > > > so it seems that I just have no patience to wait for half an hour :)
> > > > > >
> > > > > > but i still have that question:
> > > > > > is there a way to track the process if it takes too long. Could we
> > > > > > stop in the middle to see at which line it "hesitates" to move on?
> > > > > >
> > > > > > regards,
> > > > > >
> > > > > > weiwei
> > > > > >
> > > > > >
> > > > > > On 7/13/05, Weiwei Shi <helprhelp at gmail.com> wrote:
> > > > > > > Hi,
> > > > > > > I have a question on read.table.
> > > > > > >
> > > > > > > I have a dataset with 273,000 lines and 195 columns. I used the
> > > > > > > read.table to load the data into R:
> > > > > > > trn<-read.table('train1.dat', header=F, sep='|', na.strings='.')
> > > > > > > I found it takes forever.
> > > > > > >
> > > > > > > then I run 1/10 of the data (test) using read.table again. And this
> > > > > > > time it finished quickly. So, there might be something wrong in my
> > > > > > > data format causing that problem.
> > > > > > >
> > > > > > > then, my question is, is there a way in R to track at which line,
> > > > > > > something wrong occurs?
> > > > > > >
> > > > > > > Thanks,
> > > > > > >
> > > > > > > Weiwei
> > > > > > >
> > > > > > >
> > > > > > > --
> > > > > > > Weiwei Shi, Ph.D
> > > > > > >
> > > > > > > "Did you always know?"
> > > > > > > "No, I did not. But I believed..."
> > > > > > > ---Matrix III
> > > > > > >
> > > > > >
> > > > > >
> > > > > > --
> > > > > > Weiwei Shi, Ph.D
> > > > > >
> > > > > > "Did you always know?"
> > > > > > "No, I did not. But I believed..."
> > > > > > ---Matrix III
> > > > > >
> > > > > > ______________________________________________
> > > > > > R-help at stat.math.ethz.ch mailing list
> > > > > > https://stat.ethz.ch/mailman/listinfo/r-help
> > > > > > PLEASE do read the posting guide!
> > > > > http://www.R-project.org/posting-guide.html
> > > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > > --
> > > > Weiwei Shi, Ph.D
> > > >
> > > > "Did you always know?"
> > > > "No, I did not. But I believed..."
> > > > ---Matrix III
> > > >
> > >
> > >
> > > --
> > > Weiwei Shi, Ph.D
> > >
> > > "Did you always know?"
> > > "No, I did not. But I believed..."
> > > ---Matrix III
> > >
> >
> 
> 
> --
> Weiwei Shi, Ph.D
> 
> "Did you always know?"
> "No, I did not. But I believed..."
> ---Matrix III
> 


-- 
Weiwei Shi, Ph.D

"Did you always know?"
"No, I did not. But I believed..."
---Matrix III




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