Friends I'm not seeing why the following occurs:
> T1 <- (A1 - A2) %*% D > T2 <- (A1 %*% D) - (A2 %*% D) > identical(T1, T2) [1] FALSE Harold > dput(A1) new("dsCMatrix" , i = c(0L, 1L, 2L, 3L, 0L, 1L, 4L, 2L, 3L, 5L) , p = c(0L, 1L, 2L, 3L, 4L, 7L, 10L) , Dim = c(6L, 6L) , Dimnames = list(NULL, NULL) , x = c(5, 5, 5, 5, 5, 5, 10, 5, 5, 10) , uplo = "U" , factors = list() ) > dput(A2) new("dgeMatrix" , x = c(1.41313955042629, 1.23647532592053, 1.36413787785255, 0.986247245800629, 2.64961487634682, 2.35038512365318, 1.23647532592053, 1.55872699943971, 0.579347997632991, 1.62544967700677, 2.79520232536024, 2.20479767463976, 1.36413787785255, 0.579347997632991, 2.75106274522123, 0.305451379293231, 1.94348587548554, 3.05651412451446, 0.986247245800629, 1.62544967700677, 0.305451379293232, 2.08285169789937, 2.6116969228074, 2.3883030771926, 2.64961487634682, 2.79520232536024, 1.94348587548554, 2.6116969228074, 5.44481720170706, 4.55518279829294, 2.35038512365318, 2.20479767463976, 3.05651412451446, 2.3883030771926, 4.55518279829294, 5.44481720170706 ) , Dim = c(6L, 6L) , Dimnames = list(NULL, NULL) , factors = list() ) > dput(D) new("ddiMatrix" , diag = "N" , Dim = c(6L, 6L) , Dimnames = list(NULL, NULL) , x = c(5, 5, 5, 5, 10, 10) ) [[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.