Computes the base day of the year, a reference value that can be
used to group days for the computation of summary statistics. From smwrBase package.
Usage
baseDay(x, numeric = TRUE, year = c("calendar", "water", "climate"))
Arguments
x
a vector of class POSIXt, Dates, or character that represents a
date. Missing values are permitted.
numeric
a logical value; TRUE means return the numeric value
of the day, FALSE means return a factor.
year
a character string indicating the basis of the factor levels. See
Details.
Value
An integer value representing the base day number if numeric
is TRUE. Otherwise a factor with levels for every day of the year.
Details
The base day is computed such that all dates have the same reference value
regardless of whether the year is a leap year or not. If year is
"calendar," then the factor levels or day number begin on January 1; if year is
"water," then the factor levels or day number begin on October 1; and if year is
"climate," then the factor levels or day number begin on April 1.
# NOT RUN {# The default numeric resultbaseDay(c("2000-02-29", "2000-03-01", "2001-03-01"))
# The result as a factorbaseDay(c("2000-02-29", "2000-03-01", "2001-03-01"), numeric=FALSE)
# }