R help - Apr 2009 - Subsetting a vector of numerics such that standard deviation is less than 0.5 ?

> set.seed(999)
> abs(rnorm(20))
 [1] 0.28174016 1.31255963 0.79518398 0.27007049 0.27730642 0.56602374
1.87865826 1.26679114 0.96774968 1.12100936 1.32546371 0.13397739
0.93874945
[14] 0.17253810 0.95765045 1.36268625 0.06833513 0.10065765 0.90134475
2.07435711
> v <- abs(rnorm(20))
> v
 [1] 1.2285633 0.6430443 0.3597629 0.2940356 1.1252685 0.6422657
1.1067376 0.8848404 1.5540951 0.1266790 2.3826642 0.6012761 0.1793613
1.0805315 0.2468121
[16] 2.1137370 0.3705275 0.5228678 0.5178055 1.4025109

How do I select numbers from v such that the standard deviation of the
new vector is less than 0.5 ?

Daren,
what are you trying to achieve?
Why don't you want any negative numbers?
Anyway, if you only need positive values, why not:
set.seed(999)
v<-rnorm(20,mean=2,sd=0.5)
(v)
(sd(v))

Dimitri

On Wed, Apr 22, 2009 at 1:26 AM, Daren Tan <darentan76 at gmail.com>
wrote:
>> set.seed(999)
>> abs(rnorm(20))
> ?[1] 0.28174016 1.31255963 0.79518398 0.27007049 0.27730642 0.56602374
> 1.87865826 1.26679114 0.96774968 1.12100936 1.32546371 0.13397739
> 0.93874945
> [14] 0.17253810 0.95765045 1.36268625 0.06833513 0.10065765 0.90134475
> 2.07435711
>> v <- abs(rnorm(20))
>> v
> ?[1] 1.2285633 0.6430443 0.3597629 0.2940356 1.1252685 0.6422657
> 1.1067376 0.8848404 1.5540951 0.1266790 2.3826642 0.6012761 0.1793613
> 1.0805315 0.2468121
> [16] 2.1137370 0.3705275 0.5228678 0.5178055 1.4025109
>
> How do I select numbers from v such that the standard deviation of the
> new vector is less than 0.5 ?
>
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-- 
Dimitri Liakhovitski
MarketTools, Inc.
Dimitri.Liakhovitski at markettools.com