[R] how to ignore NA with "NA" or "NULL"

[Rui Barradas]

Hello again,

The complete function would be

na.fill <- function(x, y){
     # do this immediatly, may save copying
     if(all(is.na(y[1:8700,1]))) return(NA)
     i <- is.na(x[1:8700,1])
     xx <- y[1:8700,1]
     new <- data.frame(xx=xx)
     x[1:8700,1][i] <- predict(lm(x[1:8700,1]~xx, na.action=na.exclude), 
new)[i]
     x
}

Rui Barradas

Em 04-06-2012 16:05, Rui Barradas escreveu:
> Hello,
>
> 'ifelse' is vectorized, what you want is the plain 'if'.
>
> if(all(is.na(xx))) return(NA)
>
> Hope this helps,
>
> Rui Barradas
>
> Em 04-06-2012 09:56, jeff6868 escreveu:
>> Hello dear R-users,
>>
>> I have a problem in my code about ignoring NA values without removing 
>> them.
>> I'm working on a list of files. The aim is to fill one file from another
>> according to the highest correlation (correlation coeff between all my
>> files, so the file which looks like the most to the one I want to fill).
>> When I have just small gaps of NA, my function works well.
>> The problem is when I have only NAs in some files. As a consequence, it
>> cannot calculate any correlation coefficients (my previous function 
>> in the
>> case of only NAs in the file returns "NA" for the correlation 
>> coefficient),
>> and so it cannot fill it or make any calculation with it.
>>
>> Nevertheless in my work I need to keep these NA files in my list (and 
>> so to
>> keep their dimensions). Otherwise it creates some dimensions 
>> problems, and
>> my function needs to me automatic for every files.
>>
>> So my question in this post is: how to ignore (or do nothing with 
>> them if
>> you prefer) NA files with NA correlation coefficients?
>> The function for filling files (where there's the problem) is:
>>
>> na.fill<- function(x, y){
>>          i<- is.na(x[1:8700,1])
>>          xx<- y[1:8700,1]
>>          new<- data.frame(xx=xx)
>>          x[1:8700,1][i]<- predict(lm(x[1:8700,1]~xx, 
>> na.action=na.exclude),
>> new)[i]
>>          x
>>      }
>>
>> My error message is: Error in model.frame.default(formula = x[1:8700, 
>> 1] ~
>> xx, na.action = na.exclude,  :  : invalid type (NULL) for variable 'xx'
>>
>> I tried to add in the function:
>> ifelse( all(is.null(xx))==TRUE,return(NA),xx)  or
>> ifelse( all(is.null(xx))==TRUE,return(NULL),xx)
>>
>> but it still doesn't work.
>> How can I write that in my function? With NA, NULL or in another way?
>> Thank you very much for your answers
>>
>>
>> -- 
>> View this message in context: 
>> http://r.789695.n4.nabble.com/how-to-ignore-NA-with-NA-or-NULL-tp4632287.html
>> Sent from the R help mailing list archive at Nabble.com.
>>
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