https://github.com/cran/pracma
Tip revision: 26e049d70b4a1c237987e260cba68f6a9413736c authored by Hans W. Borchers on 09 April 2019, 04:10:07 UTC
version 2.2.5
version 2.2.5
Tip revision: 26e049d
eta.Rd
\name{eta}
\alias{eta}
\title{
Dirichlet Eta Function
}
\description{
Dirichlet's eta function valid in the entire complex plane.
}
\usage{
eta(z)
}
\arguments{
\item{z}{Real or complex number or a numeric or complex vector.}
}
\details{
Computes the eta function for complex arguments using a series expansion.
Accuracy is about 13 significant digits for \code{abs(z)<100},
drops off with higher absolute values.
}
\value{
Returns a complex vector of function values.
}
\references{
Zhang, Sh., and J. Jin (1996). Computation of Special Functions.
Wiley-Interscience, New York.
}
\note{
Copyright (c) 2001 Paul Godfrey for a Matlab version available on
Mathwork's Matlab Central under BSD license.
}
\seealso{
\code{\link{gammaz}}, \code{\link{zeta}}
}
\examples{
z <- 0.5 + (1:5)*1i
eta(z)
z <- c(0, 0.5+1i, 1, 1i, 2+2i, -1, -2, -1-1i)
eta(z)
}
\keyword{ specfun }