Dear, I have to compute the trace of a product between four matrices. For example, I know the matrices Wi, Wj and C, I need to compute this
-trace(Wi%*%C^-1%*%Wj%*%C^-1) I would like to avoid compute the complete matrix and after take the diagonal, something like sum(diag( solve(Wi,C)%*% solve(Wj,C))) Any idea is welcome. Thanks -- Wagner Hugo Bonat LEG - Laboratório de Estatística e Geoinformação UFPR - Universidade Federal do Paraná [[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.