Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / financial-0.4.0 / months.m

diff --git a/octave_packages/financial-0.4.0/months.m b/octave_packages/financial-0.4.0/months.m
new file mode 100644 (file)
index 0000000..ac27c98
--- /dev/null
+++ b/octave_packages/financial-0.4.0/months.m
@@ -0,0 +1,58 @@
+## Copyright (C) 2008 Bill Denney <bill@denney.ws>
+##
+## This program 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 3 of the License, or (at your option) any later
+## version.
+##
+## This program 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
+## this program; if not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {mos =} months (startdate, enddate)
+## @deftypefnx {Function File} {mos =} months (startdate, enddate, endmonthflag)
+##
+## Return the number of whole months between @var{startdate} and
+## @var{enddate}.  @var{endmonthflag} defaults to 1.
+##
+## If @var{endmonthflag} is true, then if both the @var{startdate} and
+## the @var{enddate} are end of month dates and @var{enddate} has fewer
+## days in the month than @var{startdate}, @var{endmonthflag} = 1 treats
+## @var{enddate} as the end of a month, but @var{endmonthflag} = 0 does
+## not.
+##
+## @seealso{yeardays, yearfrac}
+## @end deftypefn
+
+function mos = months (startdate, enddate, endmonthflag = 1)
+
+  if (nargin < 2 || nargin > 3)
+    print_usage ();
+  endif
+
+  s = datevec (startdate);
+  e = datevec (enddate);
+  s_eom = (s(:,3) == eomday(s(:,1), s(:,2)));
+  e_eom = (e(:,3) == eomday(e(:,1), e(:,2)));
+
+  ## Handle the end of the month correctly
+  dayadj = ((s(:,3) > e(:,3)) & endmonthflag & s_eom & e_eom);
+
+  mos = 12*(e(:,1) - s(:,1)) + (e(:,2) - s(:,2)) - (s(:,3) > e(:,3)) + dayadj;
+
+endfunction
+
+## Tests
+%!assert(months('may 31 2004', 'jun 30 2004'), 1)
+%!assert(months({'may 31 2004' 'may 30 2004'}, 'jun 30 2004'), [1;1])
+%!assert(months('may 31 2004', 'jun 30 2004', 1), 1)
+%!assert(months({'may 31 2004' 'may 30 2004'}, 'jun 30 2004', 1), [1;1])
+%!assert(months('may 31 2004', 'jun 30 2004', 0), 0)
+%!assert(months({'may 31 2004' 'may 30 2004'}, 'jun 30 2004', 0), [0;1])
+%!assert(months('jun 30 2005', 'june 30 2006'), 12)
+%!assert(months('jun 30 2005', 'june 29 2006'), 11)