R help - Jun 2007 - Expand duplicated observations

Dear all,

I am trying to  expand duplicated observations. I need to replace  
each observation in the dataset with n copies of the observation,  
where n is equal to the required expression rounded to the nearest  
integer. If the expression is less than 1 or equal to missing, it is  
interpreted as if it were 1, and the observation is retained but not  
duplicated.

Example

From
c(1,2,3)

To
c(1,2,2,3,3,3)

Thank you in advance.

Best wishes,
Martin

I think this will do what you want

x=c(1,2,3)
rep(x,x)
[1] 1 2 2 3 3 3

Regards

Francisco

M. P. Papadatos wrote:
> Dear all,
> 
> I am trying to  expand duplicated observations. I need to replace each 
> observation in the dataset with n copies of the observation, where n is 
> equal to the required expression rounded to the nearest integer. If the 
> expression is less than 1 or equal to missing, it is interpreted as if 
> it were 1, and the observation is retained but not duplicated.
> 
> Example
> 
> From
> c(1,2,3)
> 
> To
> c(1,2,2,3,3,3)
> 
> Thank you in advance.
> 
> Best wishes,
> Martin
> 
> 
> ------------------------------------------------------------------------
> 
> ______________________________________________
> 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
> and provide commented, minimal, self-contained, reproducible code.

Does this do what you want?

dat <- c(NA, 0, 3.2, 4)

fn <- function (x) {
z <- round(x)
if (is.na(x) | x <= 1) z else rep(z, each=z)
}

unlist(sapply(dat, fn))

[1] NA  0  3  3  3  4  4  4  4

HTH,

Simon.

On Wed, 2007-06-06 at 01:54 +0100, M. P. Papadatos
wrote:
> Dear all,
> 
> I am trying to  expand duplicated observations. I need to replace  
> each observation in the dataset with n copies of the observation,  
> where n is equal to the required expression rounded to the nearest  
> integer. If the expression is less than 1 or equal to missing, it is  
> interpreted as if it were 1, and the observation is retained but not  
> duplicated.
> 
> Example
> 
> From
> c(1,2,3)
> 
> To
> c(1,2,2,3,3,3)
> 
> Thank you in advance.
> 
> Best wishes,
> Martin
> 
> 
> --Apple-Mail-4-920612661--
> 
> ______________________________________________
> 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
> and provide commented, minimal, self-contained, reproducible code.
-- 
Simon Blomberg, BSc (Hons), PhD, MAppStat. 
Lecturer and Consultant Statistician 
Faculty of Biological and Chemical Sciences 
The University of Queensland 
St. Lucia Queensland 4072 
Australia

Room 320, Goddard Building (8)
T: +61 7 3365 2506 
email: S.Blomberg1_at_uq.edu.au 

The combination of some data and an aching desire for 
an answer does not ensure that a reasonable answer can 
be extracted from a given body of data. - John Tukey.