R help - Feb 2012 - function for filtering and deleting vector entries

Dear helpers

I have two data sets saved as vectors (temperature and velocity). Now I need
to "take out" a span of temperature and its corresponding velocity in
the
other vector. How can I achieve that? 

I tried to write a function,which takes a vector entry and then decides
wether to delete the temperature entry or not and  simultaneously doing so
with same entry in the velocity vector..
But somehow it's not working...could somebody please help me? 
Thanks a lot..


norm = function(Temp,v){
	for (i in 1:length(Temp)){
		
		if (Temp[i]<=16 || Temp[i] >= 38.5)
		 {Temp[-i];v[-i]}

		return(Temp,v)
	}
}


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Hello,


babyluck wrote
> 
> Dear helpers
> 
> I have two data sets saved as vectors (temperature and velocity). Now I
> need to "take out" a span of temperature and its corresponding
velocity in
> the other vector. How can I achieve that? 
> 
> I tried to write a function,which takes a vector entry and then decides
> wether to delete the temperature entry or not and  simultaneously doing so
> with same entry in the velocity vector..
> But somehow it's not working...could somebody please help me? 
> Thanks a lot..
> 
> 
> norm = function(Temp,v){
> 	for (i in 1:length(Temp)){
> 		
> 		if (Temp[i]<=16 || Temp[i] >= 38.5)
> 		 {Temp[-i];v[-i]}
> 
> 		return(Temp,v)
> 	}
> }
> 
Your function is not changing 'Temp' nor 'v', just choosing
subsets of them.
And you 'return' at the end of the first iteration...
(And you can only return one value)

Try


fun <- function(Temp, v){
	unwanted <- Temp <= 16 | Temp >= 38.5
	Temp <- Temp[!unwanted]
	v <- v[!unwanted]
	list(Temp=Temp, v=v)
}

(tt <- seq(10, 40, by=0.5))
(vv <- 1:length(tt))
fun(tt, vv)

I've changed the name because 'norm' is a  R function name. See
?norm

Hope this helps,

Rui Barradas


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Hi.

Maybe this will help you:

set.seed(1)
temp <- 1:100
v <- rnorm(100)

temp[temp<16 | temp>38]
v[temp<16 | temp>38]

Andrija

On Wed, Feb 29, 2012 at 7:09 PM, babyluck <madruga at gmx.ch>
wrote:
> Dear helpers
>
> I have two data sets saved as vectors (temperature and velocity). Now I
need
> to "take out" a span of temperature and its corresponding
velocity in the
> other vector. How can I achieve that?
>
> I tried to write a function,which takes a vector entry and then decides
> wether to delete the temperature entry or not and ?simultaneously doing so
> with same entry in the velocity vector..
> But somehow it's not working...could somebody please help me?
> Thanks a lot..
>
>
> norm = function(Temp,v){
> ? ? ? ?for (i in 1:length(Temp)){
>
> ? ? ? ? ? ? ? ?if (Temp[i]<=16 || Temp[i] >= 38.5)
> ? ? ? ? ? ? ? ? {Temp[-i];v[-i]}
>
> ? ? ? ? ? ? ? ?return(Temp,v)
> ? ? ? ?}
> }
>
>
> --
> View this message in context:
http://r.789695.n4.nabble.com/function-for-filtering-and-deleting-vector-entries-tp4432410p4432410.html
> Sent from the R help mailing list archive at Nabble.com.
>
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