[R] Assignment of values with different indexes

[arun]

HI Brian,

If ?names() work for you, then:
x <- rnorm(10)
 myindex <- seq(from = 1,to = 20, by = 2)
 myindex1<-seq(from=1,to=30,by=3)


fun1<-function(vec1,indx){
 y<-numeric()
 y<-na.omit(y[indx]<-vec1)
 names(y)<-indx
 y}


fun1(x,myindex)
 #          1            3            5            7            9           11 
 #0.430819171  0.733928361 -0.680674874  0.326196338  0.907029629 -0.462681535 
   #       13           15           17           19 
 #0.004700029  1.450397255  0.752679093  0.966159790 
 
fun1(x,myindex1)
#           1            4            7           10           13           16 
# 0.430819171  0.733928361 -0.680674874  0.326196338  0.907029629 -0.462681535 
 #         19           22           25           28 
 #0.004700029  1.450397255  0.752679093  0.966159790 
A.K.



----- Original Message -----
From: Brian Feeny <bfeeny at mac.com>
To: arun <smartpink111 at yahoo.com>
Cc: R help <r-help at r-project.org>; David Winsemius <dwinsemius at comcast.net>
Sent: Thursday, December 6, 2012 12:44 AM
Subject: Re: [R] Assignment of values with different indexes


No, because it does not assign the indexes of myindex.

If its not possible, which I am assuming its not, thats OK.  I thought that if I had say 10 observations, sequentially ordered (or any order, it doesn't matter), and I wanted to assign them specific indexes, and not have NA's, that it was possible.
I am OK with knowing that I can assign them the specific indexes, and that there will be empty spots, which are marked NA.  Most functions I would need to use can handle NA's by telling the function to ignore. I appreciate all the help that has been given.

Brian

On Dec 5, 2012, at 11:49 PM, arun <smartpink111 at yahoo.com> wrote:

> 
> 
> Hi,
> 
> Would it be okay to use:
>  y<-na.omit(y[myindex]<-x)
> y
> # [1] -1.36025132 -0.57529211  1.18132359  0.41038489  1.83108252 -0.03563686
>  #[7]  1.25267314  1.08311857  1.56973422 -0.30752939
> 
> A.K.
> 
> 
> ----- Original Message -----
> From: Brian Feeny <bfeeny at mac.com>
> To: "r-help at r-project.org help" <r-help at r-project.org>
> Cc: 
> Sent: Wednesday, December 5, 2012 9:47 PM
> Subject: [R] Assignment of values with different indexes
> 
> 
> I would like to take the values of observations and map them to a new index.  I am not sure how to accomplish this.  The result would look like so:
> 
> x[1,2,3,4,5,6,7,8,9,10]
> becomes
> y[2,4,6,8,10,12,14,16,18,20]
> 
> The "newindex" would not necessarily be this sequence, but a sequence I have stored in a vector, so it could be all kinds of values.  here is what happens:
> 
>> x <- rnorm(10)
>> myindex <- seq(from = 1,to = 20, by = 2)
>> y <- numeric()
>> y[myindex] <- x
>> y
> [1] -0.03745988          NA -0.09078822          NA  0.92484413          NA  0.32057426          NA
> [9]  0.01536279          NA  0.02200198          NA  0.37535438          NA  1.46606535          NA
> [17]  1.44855796          NA -0.05048738
> 
> So yes, it maps the values to my new indexes, but I have NA's.  The result I want would look like this instead:
> 
> 
> [1] -0.03745988          
> [3] -0.09078822          
> [5] 0.92484413          
> [7] 0.32057426        
> [9]  0.01536279          
> [11] 0.02200198          
> [13] 0.37535438          
> [15] 1.46606535        
> [17]  1.44855796          
> [19] -0.05048738
> 
> 
> and remove the NA's.  I tried this with na.omit() on x, but it looks like so:
> 
>> x <- rnorm(10)
>> myindex <- seq(from = 1,to = 20, by = 2)
>> y <- numeric()
>> y[myindex] <- na.omit(x)
>> y
> [1]  0.87399523          NA -0.39908184          NA  0.14583051          NA  0.01850755          NA
> [9] -0.47413632          NA  0.88410517          NA -1.64939190          NA  0.57650807          NA
> [17]  0.44016971          NA -0.56313802
> 
> Brian
> 
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