seq.POSIXt               package:base               R Documentation

Generate Regular Sequences of Dates

Description:

     The method for `seq' for data-time classes.

Usage:

     seq(from, to, by, length.out=NULL, along.with=NULL, ...)

Arguments:

    from: starting date. Required

      to: end date. Optional. If supplied must be after `from'.

      by: increment of the sequence. Optional. See Details.

length.out: integer, optional. desired length of the sequence.

along.with: take the length from the length of this argument.

     ...: arguments passed to or from other methods.

Details:

     `by' can be specified in several ways.

        *  A number, taken to be in seconds.

        *  A object of class `difftime'

        *  A character string, containing one of `"sec"', `"min"',
           `"hour"', `"day"', `"week"', `"month"' or `"year"'.  This
           can optionally be preceded by an integer and a space.

Value:

     A vector of class `"POSIXct"'.

See Also:

     `DateTimeClasses'

Examples:

     ## first days of years in the (commonly used) 20th century
     seq(ISOdate(1910,1,1), ISOdate(1999,1,1), "years")
     ## by month
     seq(ISOdate(2000,1,1), by="month", length=12)
     ## quarters
     seq(ISOdate(1990,1,1), ISOdate(2000,1,1), by="3 months")

