[R] Insert value in a Vector Alternately

baptiste auguie ba208 at exeter.ac.uk
Thu Feb 19 14:12:23 CET 2009


Perhaps you can try this,

> d <- c(0.00377467,  0.00377467,  0.00377467,  0.00380083,   
> 0.00380083,  0.00380083,
> 0.00380959,  0.00380959,  0.00380959,  0.00380083,  0.00380083,   
> 0.00380083)
>
> c( t( cbind(matrix(d, ncol=3, byrow=T), 0)))
>

I don't know how to avoid the transpose operation that might slow  
things down in large cases.

Hope this helps,

baptiste



On 19 Feb 2009, at 12:47, jim holtman wrote:

> How about this:
>
>> dat<- 
>> c 
>> (0.00377467,0.00377467,0.00377467,0.00380083,0.00380083,0.00380083,0.00380959 
>> ,
> + 0.00380959,0.00380959,0.00380083,0.00380083,0.00380083)
>> dat[seq(1, by=3, to=length(dat))] <- 0
>> dat
> [1] 0.00000000 0.00377467 0.00377467 0.00000000 0.00380083 0.00380083
> 0.00000000 0.00380959 0.00380959 0.00000000 0.00380083
> [12] 0.00380083
>>
>
>
> On Thu, Feb 19, 2009 at 1:47 AM, Gundala Viswanath  
> <gundalav at gmail.com> wrote:
>> Hi,
>>
>> I have a vector that look like this:
>>
>>> dat
>>            V1         V2         V3         V4         V5         V6
>> 0.00377467 0.00377467 0.00377467 0.00380083 0.00380083 0.00380083
>>            V7         V8         V9        V10        V11        V12
>> 0.00380959 0.00380959 0.00380959 0.00380083 0.00380083 0.00380083
>>
>>
>> what I want to do is to insert 0 (zero) for every 3 position  
>> yielding:
>>
>> V1   V2              V3                V4             V5    V6
>>   V7               V8
>> 0  0.00377467 0.00377467 0.00377467 0  0.00380083 0.00380083  
>> 0.00380083
>> V9   V10              V11                V12             V13    V14
>>       V15             V16
>> 0 0.00380959 0.00380959 0.00380959 0 .00380083 0.00380083 0.00380083
>>
>>
>> Is there a quick way to do it in R?
>>
>> - Gundala Viswanath
>> Jakarta - Indonesia
>>
>> ______________________________________________
>> R-help at r-project.org 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.
>>
>
>
>
> --
> Jim Holtman
> Cincinnati, OH
> +1 513 646 9390
>
> What is the problem that you are trying to solve?
>
> ______________________________________________
> R-help at r-project.org 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.

_____________________________

Baptiste Auguié

School of Physics
University of Exeter
Stocker Road,
Exeter, Devon,
EX4 4QL, UK

Phone: +44 1392 264187

http://newton.ex.ac.uk/research/emag




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