R help - Oct 2004 - How to add values to an array at any position.

Hi,

How to add values to an array at any position.
Asking because of the following:
e.g.

y<-c(0.1,NaN,0.2,NaN) #or data frame


x<-na.omit(y)

take some columns from x and
do some computation with functions which do not allow NaN 's.

After the computing add NaN's at positions stored in
attr(x,"na.action")
of the result vector.


/E


-- 
Dipl. bio-chem. Witold Eryk Wolski
MPI-Moleculare Genetic
Ihnestrasse 63-73 14195 Berlin
tel: 0049-30-83875219                 __("<    _
http://www.molgen.mpg.de/~wolski      \__/    'v'
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mail: witek96 at users.sourceforge.net    ^^     m m
      wolski at molgen.mpg.de

Witold Eryk Wolski <wolski <at> molgen.mpg.de> writes:

: 
: Hi,
: 
: How to add values to an array at any position.
: Asking because of the following:
: e.g.
: 
: y<-c(0.1,NaN,0.2,NaN) #or data frame
: 
: x<-na.omit(y)
: 
: take some columns from x and
: do some computation with functions which do not allow NaN 's.
: 
: After the computing add NaN's at positions stored in
: attr(x,"na.action")
: of the result vector.

The following adds one to each element of x and reinserts
them into y:

y[-attr(x,"na.action")] <- x+1

Witold Eryk Wolski <wolski at molgen.mpg.de> writes:
> Hi,
> 
> How to add values to an array at any position.
> Asking because of the following:
> e.g.
> 
> y<-c(0.1,NaN,0.2,NaN) #or data frame
> 
> 
> x<-na.omit(y)
> 
> take some columns from x and
> do some computation with functions which do not allow NaN 's.
> 
> After the computing add NaN's at positions stored in
> attr(x,"na.action")
> of the result vector.
You mean, something like

ix <- attr(x, "na.action")
newres <- c(res,rep(NA,length(ix))) # just to get size and mode right
newres[ix] <- NA
newres[-ix] <- res

-- 
   O__  ---- Peter Dalgaard             Blegdamsvej 3  
  c/ /'_ --- Dept. of Biostatistics     2200 Cph. N   
 (*) \(*) -- University of Copenhagen   Denmark      Ph: (+45) 35327918
~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk)             FAX: (+45) 35327907