R help - Jul 2010 - To detect the location of duplicate values

Dear R family,

I have a question about how to detect some duplicate numeric observations.
Suppose that I have two variables dataset.

order value
1  0.52
2  0.23
3  0.43
4  0.21
5  0.32
6  0.32
7  0.32
8  0.32
9  0.32
10 0.12
11 0.46
12 0.09
13 0.32
14 0.25
;
Could you help me indicate where the duplicate observations in a row
(e.g., 0.32) are?

best,
moohwan

Try this:

DF[duplicated(DF$value),]

On Mon, Jul 5, 2010 at 1:31 PM, Moohwan Kim <kmhlmj2@gmail.com> wrote:
> Dear R family,
>
> I have a question about how to detect some duplicate numeric observations.
> Suppose that I have two variables dataset.
>
> order value
> 1  0.52
> 2  0.23
> 3  0.43
> 4  0.21
> 5  0.32
> 6  0.32
> 7  0.32
> 8  0.32
> 9  0.32
> 10 0.12
> 11 0.46
> 12 0.09
> 13 0.32
> 14 0.25
> ;
> Could you help me indicate where the duplicate observations in a row
> (e.g., 0.32) are?
>
> best,
> moohwan
>
> ______________________________________________
> R-help@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.
>


-- 
Henrique Dallazuanna
Curitiba-Paraná-Brasil
25° 25' 40" S 49° 16' 22" O

	[[alternative HTML version deleted]]

Hello Moohwan,

Look at ?duplicated  for example:
> x
[1] 1 1 2 2 3 3
> duplicated(x)
[1] FALSE  TRUE FALSE  TRUE FALSE  TRUE

If your end goal is to get rid of the duplicates, take a look at ?unique
> unique(x)
[1] 1 2 3

Best Regards,

Josh

On Mon, Jul 5, 2010 at 9:31 AM, Moohwan Kim <kmhlmj2 at gmail.com>
wrote:
> Dear R family,
>
> I have a question about how to detect some duplicate numeric observations.
> Suppose that I have two variables dataset.
>
> order value
> 1 ?0.52
> 2 ?0.23
> 3 ?0.43
> 4 ?0.21
> 5 ?0.32
> 6 ?0.32
> 7 ?0.32
> 8 ?0.32
> 9 ?0.32
> 10 0.12
> 11 0.46
> 12 0.09
> 13 0.32
> 14 0.25
> ;
> Could you help me indicate where the duplicate observations in a row
> (e.g., 0.32) are?
>
> best,
> moohwan
>
> ______________________________________________
> 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.
>


-- 
Joshua Wiley
Ph.D. Student, Health Psychology
University of California, Los Angeles
http://www.joshuawiley.com/

try this"
> x
   order value
1      1  0.52
2      2  0.23
3      3  0.43
4      4  0.21
5      5  0.32
6      6  0.32
7      7  0.32
8      8  0.32
9      9  0.32
10    10  0.12
11    11  0.46
12    12  0.09
13    13  0.32
14    14  0.25
> # go both ways to capture all duplicates
> which(duplicated(x$value) | duplicated(x$value, fromLast=TRUE))
[1]  5  6  7  8  9 13
>

On Mon, Jul 5, 2010 at 12:31 PM, Moohwan Kim <kmhlmj2 at gmail.com>
wrote:
> Dear R family,
>
> I have a question about how to detect some duplicate numeric observations.
> Suppose that I have two variables dataset.
>
> order value
> 1 ?0.52
> 2 ?0.23
> 3 ?0.43
> 4 ?0.21
> 5 ?0.32
> 6 ?0.32
> 7 ?0.32
> 8 ?0.32
> 9 ?0.32
> 10 0.12
> 11 0.46
> 12 0.09
> 13 0.32
> 14 0.25
> ;
> Could you help me indicate where the duplicate observations in a row
> (e.g., 0.32) are?
>
> best,
> moohwan
>
> ______________________________________________
> 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.
>


-- 
Jim Holtman
Cincinnati, OH
+1 513 646 9390

What is the problem that you are trying to solve?

On Mon, 5 Jul 2010, Moohwan Kim wrote:
> Dear R family,
>
> I have a question about how to detect some duplicate numeric observations.
> Suppose that I have two variables dataset.
>
> order value
> 1  0.52
> 2  0.23
> 3  0.43
> 4  0.21
> 5  0.32
> 6  0.32
> 7  0.32
> 8  0.32
> 9  0.32
> 10 0.12
> 11 0.46
> 12 0.09
> 13 0.32
> 14 0.25
> ;
> Could you help me indicate where the duplicate observations in a row
> (e.g., 0.32) are?
I see you already have replies about duplicate() and unique(), which are 
very handy for the 'detect' part of your query.


But to list the locations of the duplciated elements, you might also 
benefit from using split() and Filter() like this:
> Filter( function(x) length(x)>1, split(order, value) )
$`0.32`
[1]  5  6  7  8  9 13


HTH,

Chuck


>
> best,
> moohwan
>
> ______________________________________________
> 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.
>
Charles C. Berry                            (858) 534-2098
                                             Dept of Family/Preventive Medicine
E mailto:cberry at tajo.ucsd.edu	            UC San Diego
http://famprevmed.ucsd.edu/faculty/cberry/  La Jolla, San Diego 92093-0901