R help - Dec 2010 - Sequence for repeated numbers

Hello fellows,

I would like to create a sequence for repeated numbers in a dataset. For
example:

ID <- c(1:20)
grade <- c(4,4,4,5,5,7,7,7,7,8,8,8,9,9,9,9,9,10,10,10)

Data:

ID  Grade
1   4
2   4
3   4
4   5
5   5
6   7
7   7
8   7
9   7
(...)

I would like to create a variable "sequence":

Data:
ID Grade    Sequence:
1   4          1
2   4          2
3   4          3
4   5          1
5   5          2
6   7          1
7   7          2
8   7          3
9   7          4

Any help is very much appreciate!

Thank you,

Luana Marotta

	[[alternative HTML version deleted]]

Try this:
> ord <- order(grade)
> ID <- Id[ord]
> grade <- grade[ord]
> sequence <- unlist(sapply(table(grade), FUN = function(x) 1:x), 
use.names = F)

And as a general tip, it is much easier to work with related values like 
ID and grade if they are in a data frame. Such as:
> dat <- data.frame(ID, grade)
> dat <- dat[order(grade),]
--------------------------------------
Jonathan P. Daily
Technician - USGS Leetown Science Center
11649 Leetown Road
Kearneysville WV, 25430
(304) 724-4480
"Is the room still a room when its empty? Does the room,
 the thing itself have purpose? Or do we, what's the word... imbue it."
     - Jubal Early, Firefly

r-help-bounces at r-project.org wrote on 12/01/2010 11:08:06 AM:
> [image removed] 
> 
> [R] Sequence for repeated numbers
> 
> Luana Marotta 
> 
> to:
> 
> r-help, r-help-request
> 
> 12/01/2010 11:09 AM
> 
> Sent by:
> 
> r-help-bounces at r-project.org
> 
> Hello fellows,
> 
> I would like to create a sequence for repeated numbers in a dataset. For
> example:
> 
> ID <- c(1:20)
> grade <- c(4,4,4,5,5,7,7,7,7,8,8,8,9,9,9,9,9,10,10,10)
> 
> Data:
> 
> ID  Grade
> 1   4
> 2   4
> 3   4
> 4   5
> 5   5
> 6   7
> 7   7
> 8   7
> 9   7
> (...)
> 
> I would like to create a variable "sequence":
> 
> Data:
> ID Grade    Sequence:
> 1   4          1
> 2   4          2
> 3   4          3
> 4   5          1
> 5   5          2
> 6   7          1
> 7   7          2
> 8   7          3
> 9   7          4
> 
> Any help is very much appreciate!
> 
> Thank you,
> 
> Luana Marotta
> 
>    [[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.

Hi Luana,

Try this:

ID <- 1:20
grade <- c(4, 4, 4, 5, 5, 7, 7, 7, 7, 8, 8, 8, 9, 9, 9, 9, 9, 10, 10, 10)
d <- data.frame(ID, grade)
d$Sequence <- do.call(c, sapply(rle(grade)$lengths, seq))
d

HTH,
Jorge


On Wed, Dec 1, 2010 at 11:08 AM, Luana Marotta <> wrote:
> Hello fellows,
>
> I would like to create a sequence for repeated numbers in a dataset. For
> example:
>
> ID <- c(1:20)
> grade <- c(4,4,4,5,5,7,7,7,7,8,8,8,9,9,9,9,9,10,10,10)
>
> Data:
>
> ID  Grade
> 1   4
> 2   4
> 3   4
> 4   5
> 5   5
> 6   7
> 7   7
> 8   7
> 9   7
> (...)
>
> I would like to create a variable "sequence":
>
> Data:
> ID Grade    Sequence:
> 1   4          1
> 2   4          2
> 3   4          3
> 4   5          1
> 5   5          2
> 6   7          1
> 7   7          2
> 8   7          3
> 9   7          4
>
> Any help is very much appreciate!
>
> Thank you,
>
> Luana Marotta
>
>        [[alternative HTML version deleted]]
>
> ______________________________________________
> 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.
>
	[[alternative HTML version deleted]]

Luana -
    It's probably not the most efficient way, but here's
a solution that's not dependent on the grades being sorted:
> grade <- c(4,4,4,5,5,7,7,7,7,8,8,8,9,9,9,9,9,10,10,10)
> unlist(sapply(rle(grade)$lengths,function(x)seq(1,x)))
  [1] 1 2 3 1 2 1 2 3 4 1 2 3 1 2 3 4 5 1 2 3

 					- Phil Spector
 					 Statistical Computing Facility
 					 Department of Statistics
 					 UC Berkeley
 					 spector at stat.berkeley.edu




On Wed, 1 Dec 2010, Luana Marotta wrote:
> Hello fellows,
>
> I would like to create a sequence for repeated numbers in a dataset. For
> example:
>
> ID <- c(1:20)
> grade <- c(4,4,4,5,5,7,7,7,7,8,8,8,9,9,9,9,9,10,10,10)
>
> Data:
>
> ID  Grade
> 1   4
> 2   4
> 3   4
> 4   5
> 5   5
> 6   7
> 7   7
> 8   7
> 9   7
> (...)
>
> I would like to create a variable "sequence":
>
> Data:
> ID Grade    Sequence:
> 1   4          1
> 2   4          2
> 3   4          3
> 4   5          1
> 5   5          2
> 6   7          1
> 7   7          2
> 8   7          3
> 9   7          4
>
> Any help is very much appreciate!
>
> Thank you,
>
> Luana Marotta
>
> 	[[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.
>

Try this:

id <- 1:20
grade <- c(4,4,4,5,5,7,7,7,7,8,8,8,9,9,9,9,9,10,10,10)

sequence <- ave( id, grade, FUN=seq )

# if grade is not sorted
grade2 <- sample(grade)
sequence2 <- ave( id, grade2, FUN=seq )

cbind( grade2, sequence2 )

-- 
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Luana Marotta
> Sent: Wednesday, December 01, 2010 9:08 AM
> To: r-help; r-help-request
> Subject: [R] Sequence for repeated numbers
> 
> Hello fellows,
> 
> I would like to create a sequence for repeated numbers in a dataset.
> For
> example:
> 
> ID <- c(1:20)
> grade <- c(4,4,4,5,5,7,7,7,7,8,8,8,9,9,9,9,9,10,10,10)
> 
> Data:
> 
> ID  Grade
> 1   4
> 2   4
> 3   4
> 4   5
> 5   5
> 6   7
> 7   7
> 8   7
> 9   7
> (...)
> 
> I would like to create a variable "sequence":
> 
> Data:
> ID Grade    Sequence:
> 1   4          1
> 2   4          2
> 3   4          3
> 4   5          1
> 5   5          2
> 6   7          1
> 7   7          2
> 8   7          3
> 9   7          4
> 
> Any help is very much appreciate!
> 
> Thank you,
> 
> Luana Marotta
> 
> 	[[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.