The R Project SVN R

Rev

Rev 70477 | Go to most recent revision | Show entire file | Ignore whitespace | Details | Blame | Last modification | View Log | RSS feed

Rev 70477 Rev 75395
Line 1... Line 1...
1 
% File src/library/base/man/isSymmetric.Rd
 1 
% File src/library/base/man/isSymmetric.Rd
2 
% Part of the R package, https://www.R-project.org
 2 
% Part of the R package, https://www.R-project.org
3 
% Copyright 1995-2016 R Core Team
 3 
% Copyright 1995-2018 R Core Team
4 
% Distributed under GPL 2 or later
 4 
% Distributed under GPL 2 or later
5 
 
 5 
 
6 
\name{isSymmetric}
 6 
\name{isSymmetric}
7 
\alias{isSymmetric}
 7 
\alias{isSymmetric}
8 
\alias{isSymmetric.matrix}
 8 
\alias{isSymmetric.matrix}
Line 25... Line 25...
25 
  \item{tol1}{numeric scalar >= 0.  \code{isSymmetric.matrix()}
 25 
  \item{tol1}{numeric scalar >= 0.  \code{isSymmetric.matrix()}
26 
    \sQuote{pre-tests} the first and last few rows for fast detection of
 26 
    \sQuote{pre-tests} the first and last few rows for fast detection of
27 
    \sQuote{obviously} asymmetric cases with this tolerance.  Setting it
 27 
    \sQuote{obviously} asymmetric cases with this tolerance.  Setting it
28 
    to length zero will skip the pre-tests.}
 28 
    to length zero will skip the pre-tests.}
29 
  \item{\dots}{further arguments passed to methods; the matrix method
 29 
  \item{\dots}{further arguments passed to methods; the matrix method
30 
    passes these to \code{\link{all.equal}}.}
 30 
    passes these to \code{\link{all.equal}}.  If the row and column
- 
 
 31 
    names of \code{object} are allowed to differ for the symmetry check
- 
 
 32 
    do use \code{check.attributes = FALSE}!}
31 
}
 33 
}
32 
\value{
 34 
\value{
33 
  logical indicating if \code{object} is symmetric or not.
 35 
  logical indicating if \code{object} is symmetric or not.
34 
}
 36 
}
35 
\details{
 37 
\details{
Line 56... Line 58...
56 
Z <- sqrt(matrix(-1:2 + 0i, 2)); Z <- t(Conj(Z)) \%*\% Z
 58 
Z <- sqrt(matrix(-1:2 + 0i, 2)); Z <- t(Conj(Z)) \%*\% Z
57 
Z
 59 
Z
58 
isSymmetric(Z)      # TRUE
 60 
isSymmetric(Z)      # TRUE
59 
isSymmetric(Z + 1)  # TRUE
 61 
isSymmetric(Z + 1)  # TRUE
60 
isSymmetric(Z + 1i) # FALSE -- a Hermitian matrix has a *real* diagonal
 62 
isSymmetric(Z + 1i) # FALSE -- a Hermitian matrix has a *real* diagonal
- 
 
 63 
 
- 
 
 64 
colnames(D3) <- c("X", "Y", "Z")
- 
 
 65 
isSymmetric(D3)                         # FALSE (as row and column names differ)
- 
 
 66 
isSymmetric(D3, check.attributes=FALSE) # TRUE  (as names are not checked)
61 
}
 67 
}
62 
\keyword{array}
 68 
\keyword{array}
63 
\keyword{utilities}
 69 
\keyword{utilities}