Determine the correct water year based on a calendar date.
Arguments
- dateVec
vector of dates as character ("YYYY-DD-MM"),
Date, or POSIXct. Numeric does not work.
Value
numeric vector indicating the water year
Details
This function calculates a water year based on the USGS
definition that a water year starts on October 1 of the year before,
and ends on September 30. For example, water year 2015 started on
2014-10-01 and ended on 2015-09-30.
Examples
x <- seq(as.Date("2010-01-01"), as.Date("2010-12-31"), by = "month")
calcWaterYear(x)
#> [1] 2010 2010 2010 2010 2010 2010 2010 2010 2010 2011 2011 2011
y <- c("2010-01-01", "1994-02", "1980", "2009-11-01", NA)
calcWaterYear(y)
#> [1] 2010 1994 NA 2010 NA
