| % File src/library/base/man/prod.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2007 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{prod} |
| \title{Product of Vector Elements} |
| \description{ |
| \code{prod} returns the product of all the values |
| present in its arguments. |
| } |
| \usage{ |
| prod(\dots, na.rm = FALSE) |
| } |
| \alias{prod} |
| \arguments{ |
| \item{\dots}{numeric or complex or logical vectors.} |
| \item{na.rm}{logical. Should missing values be removed?} |
| } |
| \details{ |
| If \code{na.rm} is \code{FALSE} an \code{NA} |
| value in any of the arguments will cause |
| a value of \code{NA} to be returned, otherwise |
| \code{NA} values are ignored. |
| |
| This is a generic function: methods can be defined for it |
| directly or via the \code{\link[=S3groupGeneric]{Summary}} group generic. |
| For this to work properly, the arguments \code{\dots} should be |
| unnamed, and dispatch is on the first argument. |
| |
| Logical true values are regarded as one, false values as zero. |
| For historical reasons, \code{NULL} is accepted and treated as if it |
| were \code{numeric(0)}. |
| } |
| \value{ |
| The product, a numeric (of type \code{"double"}) or complex vector of length one. |
| \strong{NB:} the product of an empty set is one, by definition. |
| } |
| \section{S4 methods}{ |
| This is part of the S4 \code{\link[=S4groupGeneric]{Summary}} |
| group generic. Methods for it must use the signature |
| \code{x, \dots, na.rm}. |
| } |
| \references{ |
| Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) |
| \emph{The New S Language}. |
| Wadsworth & Brooks/Cole. |
| } |
| \seealso{ |
| \code{\link{sum}}, |
| \code{\link{cumprod}}, \code{\link{cumsum}}. |
| |
| \sQuote{\link{plotmath}} for the use of \code{prod} in plot annotation. |
| } |
| \examples{ |
| print(prod(1:7)) == print(gamma(8)) |
| } |
| \keyword{arith} |