Hi, > Given matrix m and matrix n, I would like to compute mn[i,,j]= m[i,,j] > + n[i,,j] if either of these elements is 0. (In other words, whichever > number is nonzero.) > Else I want mn[i,,j]=(m[i,,j] + n[i,,j])/2 > I need a fast method.
m <- matrix(c(0,1,2,3,4,0,5,6,0),nrow=3,ncol=3) n <- matrix(c(1,2,0,3,0,4,0,5,6),nrow=3,ncol=3) mn <- ifelse(m==0 | n==0, m+n,(m+n)/2) Hope that helps, -- Julien Barnier Groupe de recherche sur la socialisation ENS-LSH - Lyon, France ______________________________________________ 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.
