date.mdy              package:survival              R Documentation

Convert from Julian Dates to Month, Day, and Year

Description:

     Convert a vector of Julian dates to a list of vectors with the
     corresponding values of month, day and year, and optionally
     weekday.

Usage:

     date.mdy(sdate, weekday = FALSE)

Arguments:

   sdate: a Julian date value, as returned by 'mdy.date()', number of
          days since 1/1/1960.

 weekday: if 'TRUE', then the returned list also will contain the day
          of the week (Sunday=1, Saturday=7).

Value:

     A list with components 'month', 'day', and 'year'.

References:

     Press, W. H., Teukolsky, S. A., Vetterling, W. T., and Flannery,
     B. P. (1992). _Numerical Recipes: The Art of Scientific Computing
     (Second Edition)_. Cambridge University Press.

Examples:

     day <- 7
     temp <- date.mdy(mdy.date(month = 7, day = day, year = 1960))
     ## Check for illegal dates, such as 29 Feb in a non leap year
     if (temp$day != day) {
       cat("Some illegal dates\n")
     } else {
       cat("All days are legal\n")
     }

