[R] Loop with variable index

[Benilton Carvalho]

a cleaner code would be:

sapply(2:20, function(i) c(mean=mean(x[1:i]), sd=sd(x[1:i])))

b

On Jan 30, 2008, at 3:16 PM, Henrique Dallazuanna wrote:

> Try this:
>
> x <- rnorm(20)
>
> sapply(c("sd", "mean"), function(fun)lapply(lapply(lapply(2:20, seq,
> from=1), function(.x)x[.x]), fun))
>
> On 30/01/2008, cvandy <cvandy26 at gmail.com> wrote:
>>
>> I have a list of 20 values.  The first time through a loop I want  
>> to find the
>> mean and stnd.dev. of the first two values; the second time through  
>> the loop
>> I want to find the mean and stnd. dev. of  the first 3 values, etc.  
>> until
>> the last time through the loop I want to find the mean and stnd.  
>> dev. of all
>> 20 values,  so I end up with 19 means and stnd. deviations.
>> How would I construct such a loop?
>> Thanks.
>> --
>> View this message in context: http://www.nabble.com/Loop-with-variable-index-tp15190661p15190661.html
>> Sent from the R help mailing list archive at Nabble.com.
>>
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>
>
> -- 
> Henrique Dallazuanna
> Curitiba-Paraná-Brasil
> 25° 25' 40" S 49° 16' 22" O
>
> ______________________________________________
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