[R] Converting factors to bounded random numerical data

William Dunlap wdunlap at tibco.com
Thu Oct 11 03:04:33 CEST 2012


sample(Range,1) generates 1 random number.  Change that 
(in all 3 places) to sample(Range, length(a$Z), replace=TRUE)
to get length(a$Z) random numbers in the same range.

There are other ways to do this with less typing.

Bill Dunlap
Spotfire, TIBCO Software
wdunlap tibco.com


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org] On Behalf
> Of KoopaTrooper
> Sent: Wednesday, October 10, 2012 5:09 PM
> To: r-help at r-project.org
> Subject: [R] Converting factors to bounded random numerical data
> 
> I have a data set (a) with 3 columns (X,Y,Z). The first 2 columns are
> numerical. The third column (Z) is a factor with three levels ("A","B","C").
> What I want to do is turn each of the "A's" into different random numbers
> between 1 and 4, "B's" into a random number between 5 and 8, etc.
> 
> I tried this:
> 
> a$Z<-
> ifelse(a$Z=="A",sample(1:4,1),ifelse(a$Z=="B",sample(5:9,1),ifelse(a$Z=="C",sample(10:1
> 2,1),"")
> 
> That almost worked but changed all the A's to the same random number. I want
> a different random number for each "A". Ideas?
> 
> 
> 
> 
> 
> 
> 
> 
> 
> --
> View this message in context: http://r.789695.n4.nabble.com/Converting-factors-to-
> bounded-random-numerical-data-tp4645798.html
> Sent from the R help mailing list archive at Nabble.com.
> 
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