If there weren't an analytic solution to your problem, then you could build a vector of the answers from 1 to the maximum in the matrix. Call that 'wtvec'. Then:
ans <- array(NA, dim(A), dimnames(A)) ans[] <- wtvec[as.vector(A)] should get you what you want. Patrick Burns [EMAIL PROTECTED] +44 (0)20 8525 0696 http://www.burns-stat.com (home of S Poetry and "A Guide for the Unwilling S User") Tim Smith wrote: >Hi, > >I have a 7000x7000 matrix, and each element is an integer. For each element, I >want to apply the function : > >wt <- 0 > for(q in 1:count){ > wt <- wt + 0.5^(q-1) >} > >I get the value of 'count' from the elements in the matrix , and want to store >the corresponding 'wt' value for that element. > >I suppose I could loop through the matrix, and apply the function to each >element but this would take a really really long time. Are there any quicker >ways to get the same result? > >many thanks, > >Tim > > >--------------------------------- > > > [[alternative HTML version deleted]] > >______________________________________________ >[email protected] mailing list >https://stat.ethz.ch/mailman/listinfo/r-help >PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > > > > > ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
