Re: [R] How to read a row dataset one by one

From: Henrik Bengtsson <hb_at_maths.lth.se>
Date: Fri 10 Jun 2005 - 21:00:44 EST

Jan,

I'm not sure what you asking for. First, you cannot make read.table() to output verbose message at every line read. Second, if you have trouble to read you file, which looks like what you are showing, then read ?read.table carefully. Most likely you wish to add argument header=TRUE and sep="\t" (if it is a tab-delimited file).

/Henrik

Jan Sabee wrote:
> For Henrik and Clark, thanks for your help.
> Then If I load to dataframe,
> MM16 <- read.table("G:\\Stuff\\data\\MM16.txt")
> MM16
> x1 x2 x3 x4 x5 y
> a b a c c M1
> c b b c c M4
> c c a c c M2
> c a c a a M2
> c c a a a M1
> c a b c a M3
> c c a b c M3
> c a c a b M2
> c c a b a M1
>
> How can I do it.
> Thanks again for your help.
> Jan Sabee
>
> On 6/10/05, Henrik Bengtsson <hb@maths.lth.se> wrote:
>

>>Open a connection a read line by line from that one, e.g.
>>
>>myReadPrint <- function(pathname, ...) {
>>   con <- file(pathname, open="r")
>>   on.exit(close(con)) # Guarantees to close connection!
>>
>>   count <- 0;
>>   while(TRUE) {
>>     line <- scan(con, sep="\t", nlines=1, fill=TRUE,
>>                                        quiet=TRUE, what="raw");
>>     # Alternatively, just...
>>     # line <- readLines(con, n=1)
>>     if (length(line) == 0)
>>       break;
>>     count <- count + 1;
>>     cat("read row no ", count, ",\n", sep="");
>>     print(line);
>>   }
>>}
>>
>>See ?file for more details.
>>
>>/Henrik
>>
>>Clark Allan wrote:
>>
>>>use a loop associated with the scan function.
>>>
>>>for (i in 1:9)
>>>{
>>>
>>>print(scan(file="c:/a.txt",sep="\t",skip=i,nlines=1,fill=T,quiet=T,what="raw"))
>>>}
>>>
>>>
>>>this works but there has to be a better solution
>>>
>>>
>>>
>>>Jan Sabee wrote:
>>>
>>>
>>>>Dear all,
>>>>How to read a row dataset one by one and then print it.
>>>>
>>>>x1 x2 x3 x4 x5   y
>>>>a  b  a  c  c    M1
>>>>c  b  b  c  c    M4
>>>>c  c  a  c  c    M2
>>>>c  a  c  a  a    M2
>>>>c  c  a  a  a    M1
>>>>c  a  b  c  a    M3
>>>>c  c  a  b  c    M3
>>>>c  a  c  a  b    M2
>>>>c  c  a  b  a    M1
>>>>
>>>>I need a result like
>>>>read row no 1,
>>>>[1] a  b  a  c  c    M1
>>>>read row no 2,
>>>>[1] c  b  b  c  c    M4
>>>>.
>>>>.
>>>>.
>>>>the last row,
>>>>[1] c  c  a  b  a    M1
>>>>
>>>>Kind regards,
>>>>Jan Sabee
>>>>
>>>>______________________________________________
>>>>R-help@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
>>>>
>>>>
>>>>------------------------------------------------------------------------
>>>>
>>>>______________________________________________
>>>>R-help@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
>>
>>

>
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>

R-help@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 Received on Fri Jun 10 21:10:37 2005

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