--- a/scripts/ChangeLog	Fri Mar 10 17:27:50 2006 +0000
+++ b/scripts/ChangeLog	Fri Mar 10 17:43:38 2006 +0000
@@ -1,3 +1,8 @@
+2006-03-10  Paul Kienzle  <pkienzle@users.sf.net>
+
+	* time/etime.m: Use datenum to support times spanning year boundaries.
+	* time/datenum.m: New function to compute day number from time.
+
 2006-03-09  John W. Eaton  <jwe@octave.org>
 
 	* miscellaneous/unix.m, plot/print.m:

--- a/scripts/time/datenum.m	Fri Mar 10 17:27:50 2006 +0000
+++ b/scripts/time/datenum.m	Fri Mar 10 17:43:38 2006 +0000
@@ -1,57 +1,93 @@
+## Copyright (C) 2006 Paul Kienzle
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 2, or (at your option)
+## any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+## General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, write to the Free
+## Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+## 02110-1301, USA.
+
 ## -*- texinfo -*-
-## @deftypefn {Function File} {} datenum(Y, M, D [, h , m [, s]])
-## @deftypefnx {Function File} {} datenum('date' [, P])
+## @deftypefn {Function File} {} datenum (@var{year}, @var{month}, @var{day})
+## @deftypefnx {Function File} {} datenum (@var{year}, @var{month}, @var{day}, @var{hour})
+## @deftypefnx {Function File} {} datenum (@var{year}, @var{month}, @var{day}, @var{hour}, @var{minute})
+## @deftypefnx {Function File} {} datenum (@var{year}, @var{month}, @var{day}, @var{hour}, @var{minute}, @var{second})
+## @deftypefnx {Function File} {} datenum (@code{"date"})
+## @deftypefnx {Function File} {} datenum (@code{"date"}, @var{p})
 ## Returns the specified local time as a day number, with Jan 1, 0000
-## being day 1. By this reckoning, Jan 1, 1970 is day number 719529.  
-## The fractional portion, corresponds to the portion of the specified day.
+## being day 1.  By this reckoning, Jan 1, 1970 is day number 719529.  
+## The fractional portion, @var{p}, corresponds to the portion of the
+## specified day.
 ##
+## Notes:
+##
+## @itemize
+## @item
 ## Years can be negative and/or fractional.
+## @item
 ## Months below 1 are considered to be January.
+## @item
 ## Days of the month start at 1.
+## @item
 ## Days beyond the end of the month go into subsequent months.
+## @item
 ## Days before the beginning of the month go to the previous month.
+## @item
 ## Days can be fractional.
+## @end itemize
 ##
-## WARNING: this function does not attempt to handle Julian
+## @strong{Warning:} this function does not attempt to handle Julian
 ## calendars so dates before Octave 15, 1582 are wrong by as much
 ## as eleven days.  Also be aware that only Roman Catholic countries
 ## adopted the calendar in 1582.  It took until 1924 for it to be 
 ## adopted everywhere.  See the Wikipedia entry on the Gregorian 
 ## calendar for more details.
 ##
-## WARNING: leap seconds are ignored.  A table of leap seconds
+## @strong{Warning:} leap seconds are ignored.  A table of leap seconds
 ## is available on the Wikipedia entry for leap seconds.
 ## @seealso{date, clock, now, datestr, datevec, calendar, weekday}
 ## @end deftypefn
 
 ## Algorithm: Peter Baum (http://vsg.cape.com/~pbaum/date/date0.htm)
 ## Author: Paul Kienzle
-## This program is granted to the public domain.
 
-function [days,secs] = datenum(Y,M,D,h,m,s)
+function [days, secs] = datenum (Y, M, D, h, m, s)
+
   ## Days until start of month assuming year starts March 1.
-  persistent monthstart = [306;337;0;31;61;92;122;153;184;214;245;275];
+  persistent monthstart = [306; 337; 0; 31; 61; 92; 122; 153; 184; 214; 245; 275];
 
-  if nargin == 0 || (nargin > 2  && ischar(Y)) || nargin > 6
-    usage("n=datenum('date' [, P]) or n=datenum(Y, M, D [, h, m [, s]])");
+  if (nargin == 0 || (nargin > 2  && ischar (Y)) || nargin > 6)
+    usage ("n = datenum ('date' [, P]) or n = datenum (Y, M, D [, h, m [, s]])");
   endif
-  if ischar(Y)
-    if nargin < 2, M=[]; endif
-    error('string form of dates not yet supported');
-    ## [Y,M,D,h,m,s] = datevec(Y,M);
+  if (ischar (Y))
+    if (nargin < 2)
+      M = [];
+    endif
+    error ("string form of dates not yet supported");
+    ## [Y, M, D, h, m, s] = datevec (Y, M);
   else
-    if nargin < 6, s = 0; endif
-    if nargin < 5, m = 0; endif
-    if nargin < 4, h = 0; endif
-    if nargin == 1
-      nc = columns(Y);
-      if nc > 6 || nc < 3,
-        error("expected date vector containing [Y,M,D,h,m,s]");
+    if (nargin < 6) s = 0; endif
+    if (nargin < 5) m = 0; endif
+    if (nargin < 4) h = 0; endif
+    if (nargin == 1)
+      nc = columns (Y);
+      if (nc > 6 || nc < 3)
+        error ("expected date vector containing [Y, M, D, h, m, s]");
       endif
-      s=m=h = 0;
-      if nc >= 6, s = Y(:,6); endif
-      if nc >= 5, m = Y(:,5); endif
-      if nc >= 4, h = Y(:,4); endif
+      s = m = h = 0;
+      if (nc >= 6) s = Y(:,6); endif
+      if (nc >= 5) m = Y(:,5); endif
+      if (nc >= 4) h = Y(:,4); endif
       D = Y(:,3);
       M = Y(:,2);
       Y = Y(:,1);
@@ -62,14 +98,14 @@
 
   ## Set start of year to March by moving Jan. and Feb. to previous year.
   ## Correct for months > 12 by moving to subsequent years.
-  Y += fix((M-14)/12);
+  Y += fix ((M-14)/12);
 
   ## Lookup number of days since start of the current year.
   D += monthstart (mod (M-1,12) + 1) + 60;
 
   ## Add number of days to the start of the current year. Correct
   ## for leap year every 4 years except centuries not divisible by 400.
-  D += 365*Y+floor(Y/4)-floor(Y/100)+floor(Y/400);
+  D += 365*Y + floor (Y/4) - floor (Y/100) + floor (Y/400);
 
   ## Add fraction representing current second of the day.
   days = D + (h+(m+s/60)/60)/24;