Program GREG2JUL

Usage

    greg2jul <Gregorian date>

or, alternately,

    greg2jul [ yesterday | today | tomorrow ]

    greg2jul --help

Summary

Convert Gregorian-style date or yesterday, today, or tomorrow command line argument to Julian style YYYYDDD and echo the result to standard output as a single 7-digit integer formatted YYYYDDD.

Options for the Gregorian-style (calendar) date are:

<Mon> <DD> <YYYY> [3-letter month-abbreviation), e.g., Feb 12 2010
<MM> <DD> <YYYY>, e.g., 02 12 2010
<YYYYMMDD>, e.g., 20100212
YESTERDAY
TODAY
TOMORROW

If --help is the argument, writes the USAGE screen and exits.

Not case sensitive.

Examples

Some sample executions of this program are as indicated below (where, for purposes of illustration, "today", as I write, is January 29, 2014).

(Note that in shell-scripting, the back-quote character means "the result of evaluating the enclosed command" so that the fourth example below sets shell variable foo to the result of executing the indicated greg2jul command.)

     % greg2jul 20140129
     2014029

     % greg2jul YESTERDAY
     2014028

     % greg2jul tomorrow
     2014030

     % set foo = `greg2jul 19970503`
     % echo ${foo}
     1997123

     % greg2jul FEB 2 2014
     2014033

     % greg2jul 02 28 2014
     2014059

     % greg2jul --help
         %  greg2jul <calendar date>
         or
         %  set gdate = ``greg2jul 20140201` 

         Options for <calendar date>
              <MON> <DD> <YYYY>, e.g., Feb 12 2010
              <MM>  <DD> <YYYY>, e.g., 02 12 2010
              <YYYYMMDD>       , e.g., 20100212
              TODAY
              YESTERDAY
              TOMORROW
              --HELP
         Case is NOT significant.
         Use 3-letter month-names ("JAN", "FEB", etc.)
         Output format is 7-digit integer YYYYDDD

Program GREG2JUL

Usage

Summary

Examples

See Also