Try this:
"%add%" <- function(x1, x2)
{
dim1 <- dim(x1)
dim2 <- dim(x2)
seq1 <- list();for(i in 1:length(dim1)) seq1[[i]]=seq(dim1[i])
filter1 <- paste(seq1, collapse=",")
cmd1 <- paste("out[", filter1, "]", sep="")
seq2 <- list();for(i in 1:length(dim2)) seq2[[i]]=seq(dim2[i])
filter2 <- paste(seq2, collapse=",")
cmd2 <- paste("out[", filter2, "]", sep="")
out <- array(0, dim=pmax(dim1,dim2))
eval(parse(text=paste(cmd1, "<-", cmd1, "+ x1")))
eval(parse(text=paste(cmd2, "<-", cmd2, "+ x2")))
out
}
x1 <- array(round(5*runif(30)), dim=c(2,3,5))
x2 <- array(round(5*runif(24)), dim=c(3,4,2))
x <- x1 %add% x2
You probably want to add a check to make the dimensions the same, and the
code needs tidying, but you get the idea.
Regards,
Richie.
Mathematical Sciences Unit
HSL
[EMAIL PROTECTED] wrote on 19/12/2007 09:26:44:
> Hi
>
> suppose I have two arrays x1,x2 of dimensions a1,b1,c1 and
> a2,b2,c2 respectively.
>
> I want x = x1 "+" x2 with dimensions c(max(a1,a2), max(b1,b2),max
> (c1,c2))
>
> with
>
> x[a,b,c] = x1[a1,b1,c1] + x2[a2,b2,c2] if a <=min(a1,a2) , b<=min
> (b1,b2), c<=min(c1,c2)
>
> and the other bits either x1 or x2 or zero according to whether the
> coordinates
> are "in range" for x1 or x2 or neither.
>
> The answer has to work for arbitrary-dimensioned arrays.
>
> toy example follows (matrices):
>
>
> > x1
> [,1] [,2] [,3] [,4] [,5]
> [1,] 1 3 5 7 9
> [2,] 2 4 6 8 10
> > x2
> [,1] [,2] [,3]
> [1,] 1 4 7
> [2,] 2 5 8
> [3,] 3 6 9
> > x
> [,1] [,2] [,3] [,4] [,5]
> [1,] 2 7 12 7 9
> [2,] 4 9 14 8 10
> [3,] 3 6 9 0 0
> >
>
>
> Note the zeros at lower-right.
>
>
> Is there a ready-made solution to this?
>
>
>
>
>
> --
> Robin Hankin
> Uncertainty Analyst and Neutral Theorist,
> National Oceanography Centre, Southampton
> European Way, Southampton SO14 3ZH, UK
> tel 023-8059-7743
>
> ______________________________________________
> R-help@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.
------------------------------------------------------------------------
ATTENTION:
This message contains privileged and confidential inform...{{dropped:20}}
______________________________________________
R-help@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.
