R help - Feb 2010 - Dividing one column of form xx-yy into two columns, xx and yy

I have a data set where one column consists of two numerical factors,
separated by a "-".
So my data looks something like this:

43-156
43-43
1267-18
.
.
.

There are additional columns consisting of single factors as well, so
reading the csv file (where the data is stored) with the sep="-"
addition
won't work since the rest of the factors are separated by commas.
So first of all, is there any way to import a file which is separated by
","
OR "-"?

If this is not possible, does anyone have any ideas how I could go about to
separate these? I could use a text editor to replace the - with , and
import, but I would prefer doing this inside of R so that making a script
could be used in the future.

Just to clarify, I would like the above to turn out as two separate columns
(or vectors) where the first in this would be (43,43,1267,....) and the
second (156,43,18,.....)
The dataset is rather large, with a few hundred thousand lines, so it would
be preferable to keep resource intensive methods to a minimum if possible.

Thanks in advance!
Mike

	[[alternative HTML version deleted]]

Tena koe Mike

?strsplit

for post input separation.  AFAIK there is one cannot specify multiple
separators, but:

library(fortunes)
fortune('this is R')

HTH ....

Peter Alspach 
> -----Original Message-----
> From: r-help-bounces at r-project.org 
> [mailto:r-help-bounces at r-project.org] On Behalf Of ZeMajik
> Sent: Tuesday, 9 February 2010 12:32 p.m.
> To: R mailing list
> Subject: [R] Dividing one column of form xx-yy into two 
> columns, xx and yy
> 
> I have a data set where one column consists of two numerical 
> factors, separated by a "-".
> So my data looks something like this:
> 
> 43-156
> 43-43
> 1267-18
> .
> .
> .
> 
> There are additional columns consisting of single factors as 
> well, so reading the csv file (where the data is stored) with 
> the sep="-" addition won't work since the rest of the factors
> are separated by commas.
> So first of all, is there any way to import a file which is 
> separated by ","
> OR "-"?
> 
> If this is not possible, does anyone have any ideas how I 
> could go about to separate these? I could use a text editor 
> to replace the - with , and import, but I would prefer doing 
> this inside of R so that making a script could be used in the future.
> 
> Just to clarify, I would like the above to turn out as two 
> separate columns (or vectors) where the first in this would 
> be (43,43,1267,....) and the second (156,43,18,.....) The 
> dataset is rather large, with a few hundred thousand lines, 
> so it would be preferable to keep resource intensive methods 
> to a minimum if possible.
> 
> Thanks in advance!
> Mike
> 
> 	[[alternative HTML version deleted]]
> 
> ______________________________________________
> R-help at 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.
>

Here is one way.
> dat
       V1
1  43-156
2   43-43
3 1267-18
> dat <- within(dat, {
+ m <- do.call("rbind", strsplit(as.character(V1), "-"))
+ XX <- as.numeric(m[,1])
+ YY <- as.numeric(m[,2])
+ rm(m)
+ })
> dat
       V1  YY   XX
1  43-156 156   43
2   43-43  43   43
3 1267-18  18 1267
>  

Bill Venables
CSIRO/CMIS Cleveland Laboratories


-----Original Message-----
From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
On Behalf Of ZeMajik
Sent: Tuesday, 9 February 2010 9:32 AM
To: R mailing list
Subject: [R] Dividing one column of form xx-yy into two columns, xx and yy

I have a data set where one column consists of two numerical factors,
separated by a "-".
So my data looks something like this:

43-156
43-43
1267-18
.
.
.

There are additional columns consisting of single factors as well, so
reading the csv file (where the data is stored) with the sep="-"
addition
won't work since the rest of the factors are separated by commas.
So first of all, is there any way to import a file which is separated by
","
OR "-"?

If this is not possible, does anyone have any ideas how I could go about to
separate these? I could use a text editor to replace the - with , and
import, but I would prefer doing this inside of R so that making a script
could be used in the future.

Just to clarify, I would like the above to turn out as two separate columns
(or vectors) where the first in this would be (43,43,1267,....) and the
second (156,43,18,.....)
The dataset is rather large, with a few hundred thousand lines, so it would
be preferable to keep resource intensive methods to a minimum if possible.

Thanks in advance!
Mike

	[[alternative HTML version deleted]]

______________________________________________
R-help at 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.

If you are willing to use an outside utility, tr, and you are using
UNIX then you can pipe the input through it so read.csv sees all the
dashes as commas:
> cat("A,B-C,D
+ 1,2-3,4
+ 5,6-7,8
+ ", file = "dashcomma.dat")
>
> read.csv(pipe("tr - , < dashcomma.dat"))
  A B C D
1 1 2 3 4
2 5 6 7 8

On Windows tr is available from Duncan Murdoch's Rtools distribution.
(google to find it).



On Mon, Feb 8, 2010 at 6:31 PM, ZeMajik <zemajik at gmail.com>
wrote:
> I have a data set where one column consists of two numerical factors,
> separated by a "-".
> So my data looks something like this:
>
> 43-156
> 43-43
> 1267-18
> .
> .
> .
>
> There are additional columns consisting of single factors as well, so
> reading the csv file (where the data is stored) with the sep="-"
addition
> won't work since the rest of the factors are separated by commas.
> So first of all, is there any way to import a file which is separated by
","
> OR "-"?
>
> If this is not possible, does anyone have any ideas how I could go about to
> separate these? I could use a text editor to replace the - with , and
> import, but I would prefer doing this inside of R so that making a script
> could be used in the future.
>
> Just to clarify, I would like the above to turn out as two separate columns
> (or vectors) where the first in this would be (43,43,1267,....) and the
> second (156,43,18,.....)
> The dataset is rather large, with a few hundred thousand lines, so it would
> be preferable to keep resource intensive methods to a minimum if possible.
>
> Thanks in advance!
> Mike
>
> ? ? ? ?[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.
>