Hi RUsers, I am struggling to come up with an efficient vectorized way to convert 20Kx20K covariance matrix to a Euclidian distance matrix as a surrogate for dissimilarity matrix. Hopefully I can apply multidimensional scaling for mapping these 20K points (commercial products).
I understand that Distance(ij) = sigma(i) + sigma(j) - 2cov(ij). Without replying on a slow loop, I appreciate if anyone can help me out with a better idea - guess lapply? Thank you very much. Taka [[alternative HTML version deleted]] ______________________________________________ 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.