| forceSymmetric {Matrix} | R Documentation |
Force x (inheriting from Matrix class) to
symmetricMatrix, without a symmetry check
(which is applied for all as(x, "symmetricMatrix")
alikes).
forceSymmetric(x, uplo)
x |
a (classed) square matrix. |
uplo |
optional string, "U" or "L".
The default is "U" unless x already has a uplo
slot (i.e., when it is symmetricMatrix,
or triangularMatrix), where the default will
be x@uplo. |
a square matrix inheriting from class
symmetricMatrix.
symmpart for the symmetric part, or the coercions
as(x, <symmetricMatrix class>).
## Hilbert matrix i <- 1:6 h6 <- 1/outer(i - 1L, i, "+") sd <- sqrt(diag(h6)) hh <- t(h6/sd)/sd # theoretically symmetric isSymmetric(hh, tol=0) # FALSE; hence try( as(hh, "symmetricMatrix") ) # fails, but this works fine: H6 <- forceSymmetric(hh) ## result can be pretty surprising: (M <- Matrix(1:36, 6)) forceSymmetric(M) # symmetric, hence very different in lower triangle (tm <- tril(M)) forceSymmetric(tm)