| % File src/library/base/man/seq.Date.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2017 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{seq.Date} |
| \alias{seq.Date} |
| \title{Generate Regular Sequences of Dates} |
| \description{ |
| The method for \code{\link{seq}} for objects of class class |
| \code{"\link{Date}"} representing calendar dates. |
| } |
| \usage{ |
| \method{seq}{Date}(from, to, by, length.out = NULL, along.with = NULL, \dots) |
| } |
| \arguments{ |
| \item{from}{starting date. Required} |
| \item{to}{end date. Optional.} |
| \item{by}{increment of the sequence. Optional. See \sQuote{Details}.} |
| \item{length.out}{integer, optional. Desired length of the sequence.} |
| \item{along.with}{take the length from the length of this argument.} |
| \item{\dots}{arguments passed to or from other methods.} |
| } |
| \details{ |
| \code{by} can be specified in several ways. |
| \itemize{ |
| \item A number, taken to be in days. |
| \item A object of class \code{\link{difftime}} |
| \item A character string, containing one of \code{"day"}, |
| \code{"week"}, \code{"month"}, \code{"quarter"} or \code{"year"}. |
| This can optionally be preceded by a (positive or negative) integer |
| and a space, or followed by \code{"s"}. |
| |
| See \code{\link{seq.POSIXt}} for the details of \code{"month"}. |
| } |
| } |
| \value{ |
| A vector of class \code{"Date"}. |
| } |
| \seealso{\code{\link{Date}}} |
| |
| \examples{ |
| ## first days of years |
| seq(as.Date("1910/1/1"), as.Date("1999/1/1"), "years") |
| ## by month |
| seq(as.Date("2000/1/1"), by = "month", length.out = 12) |
| ## quarters |
| seq(as.Date("2000/1/1"), as.Date("2003/1/1"), by = "quarter") |
| |
| ## find all 7th of the month between two dates, the last being a 7th. |
| st <- as.Date("1998-12-17") |
| en <- as.Date("2000-1-7") |
| ll <- seq(en, st, by = "-1 month") |
| rev(ll[ll > st & ll < en]) |
| } |
| \keyword{manip} |
| \keyword{chron} |