[R] Sequence for repeated numbers

[Jonathan P Daily]

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]]
> 
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