R help - Aug 2005 - read a table ignoring specific rows ?

Dear R users,
First of all sorry for this question, surely quite naive.
(I searched on the R site but was unable to find by myself).

I have a table, called infile :
1 2 3
4 5 6
7 8 9

I would like to read it and ignore the rows with 1st element > 3
I do it now with a for loop, and it's ok,
but I was expecting something simpler, like :

intable  = read.table(infile);
newtable = intable[isgoodrow(intable)];

where :   isgoodrow = function(therow)
{if (therow$V1 > 3) return(F) else return(T);};

(... but this don't work).

So, could somebody please tell me if there is a way to read
a table ignoring specific rows, without using a for loop ?
... and if yes how ?

Thanks
Vincent

why don't you just do

intable<-intable[intable$V1<=3,]

On Mon, 22 Aug 2005 vincent at 7d4.com wrote:
> Dear R users,
> First of all sorry for this question, surely quite naive.
> (I searched on the R site but was unable to find by myself).
>
> I have a table, called infile :
> 1 2 3
> 4 5 6
> 7 8 9
>
> I would like to read it and ignore the rows with 1st element > 3
> I do it now with a for loop, and it's ok,
> but I was expecting something simpler, like :
>
> intable  = read.table(infile);
> newtable = intable[isgoodrow(intable)];
>
> where :   isgoodrow = function(therow)
> {if (therow$V1 > 3) return(F) else return(T);};
>
> (... but this don't work).
>
> So, could somebody please tell me if there is a way to read
> a table ignoring specific rows, without using a for loop ?
> ... and if yes how ?
>
> Thanks
> Vincent
>
> ______________________________________________
> 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
>

Can you read in the entire file as a data.frame; and then construct a
new data.frame which excludes some rows?

perhaps something along the lines of...
> fred.file <- data.frame()
> fred.file <- edit(fred.file)
> fred.file
  colA colB colC
1    1    4    2
2    2    3    3
3    3    5    4
4    4    3    3
5    5    2   25
> fred.new <- fred.file[fred.file$colC <= 3,]
> fred.new
  colA colB colC
1    1    4    2
2    2    3    3
4    4    3    3

s/


On 22/08/05, vincent at 7d4.com <vincent at 7d4.com>
wrote:
> Dear R users,
> First of all sorry for this question, surely quite naive.
> (I searched on the R site but was unable to find by myself).
> 
> I have a table, called infile :
> 1 2 3
> 4 5 6
> 7 8 9
> 
> I would like to read it and ignore the rows with 1st element > 3
> I do it now with a for loop, and it's ok,
> but I was expecting something simpler, like :
> 
> intable  = read.table(infile);
> newtable = intable[isgoodrow(intable)];
> 
> where :   isgoodrow = function(therow)
> {if (therow$V1 > 3) return(F) else return(T);};
> 
> (... but this don't work).
> 
> So, could somebody please tell me if there is a way to read
> a table ignoring specific rows, without using a for loop ?
> ... and if yes how ?
> 
> Thanks
> Vincent
> 
> ______________________________________________
> 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
>

Thank you very much to all of you.
Sorry once more for this too simple question.
I have to improve my knowledge about the syntax !
Thanks
Vincent