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# View of /pkg/man/tcrossprod.Rd

Fri Nov 12 21:02:51 2004 UTC (14 years, 10 months ago) by bates
File size: 916 byte(s)
update methods
\name{tcrossprod}
\docType{methods}
\alias{tcrossprod-methods}
\alias{tcrossprod,cscMatrix-method}
\alias{tcrossprod}
\title{Cross-product of transpose}
\description{
Take the cross-product of the transpose of a matrix.
This is formally equivalent to, but faster than, the
call \code{x \%*\% t(x)}.
}
\usage{
tcrossprod(x)
}
\arguments{
\item{x}{a matrix-like object}
}
\details{
For some classes in the \code{Matrix} package, such as the
\code{\link{cscMatrix-class}}, it is much faster to calculate the
cross-product of the transpose directly instead of calculating the
transpose first and then its cross-product.
}
\value{
An object of an appropriate symmetric matrix class.
}
\section{Methods}{
\describe{
\item{x = "cscMatrix"}{method for compressed, sparse,
column-oriented matrices.}
}
}