function C = lt(A,B)  % --*-- Unitary tests --*--

% Overloads the < operator for dates objects.
%
% INPUTS 
%  o A    dates object with n or 1 elements.
%  o B    dates object with n or 1 elements.
%
% OUTPUTS 
%  o C    column vector of max(n,1) elements (zeros or ones).

% Copyright (C) 2013 Dynare Team
%
% This file is part of Dynare.
%
% Dynare 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.
%
% Dynare 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 Dynare.  If not, see <http://www.gnu.org/licenses/>.

if ~isequal(nargin,2)
    error('dates::lt: I need exactly two input arguments!')
end

if ~isa(A,'dates') || ~isa(B,'dates')
    error(['dates::lt: Input arguments ''' inputname(1) ''' and ''' inputname(2) ''' have to be a dates objects!'])
end

if ~isequal(A.freq,B.freq)
    C = 0;
    return
end

if isequal(A.ndat, B.ndat)
    C = NaN(A.ndat,1);
    for i=1:A.ndat
        C(i) = compare_vectors(@lt, A.time(i,:), B.time(i,:));
    end
else
    if isequal(A.ndat,1) && isequal(B.ndat,1)
        C = compare_vectors(@lt, A.time, B.time);
    elseif isequal(A.ndat,1)
        C = NaN(B.ndat,1);
        for i=1:B.ndat
            C(i) = compare_vectors(@lt, A.time, B.time(i,:));
        end
    elseif isequal(B.ndat,1)
        C = NaN(A.ndat,1);
        for i=1:A.ndat
            C(i) = compare_vectors(@lt, A.time(i,:), B.time);
        end
    else
        C = 0;
    end
end

%@test:1
%$ % Define some dates
%$ date_2 = '1950Q2';
%$ date_3 = '1950Q3';
%$ date_4 = '1950Q1';
%$ date_5 = '1949Q2';
%$
%$ % Call the tested routine.
%$ d2 = dates(date_2);
%$ d3 = dates(date_3);
%$ d4 = dates(date_4);
%$ d5 = dates(date_5);
%$ i1 = (d2<d3);
%$ i2 = (d3<d4);
%$ i3 = (d4<d2);
%$ i4 = (d5<d4);
%$
%$ % Check the results.
%$ t(1) = dyn_assert(i1,1);
%$ t(2) = dyn_assert(i2,0);
%$ t(3) = dyn_assert(i3,1);
%$ t(4) = dyn_assert(i4,1);
%$ T = all(t);
%@eof:1

%@test:2
%$ % Define some dates
%$ B1 = '1945Q1';
%$ B2 = '1945Q2';
%$ B3 = '1945Q3';
%$ B4 = '1945Q4';
%$ B5 = '1950Q1';
%$
%$ % Create dates objects.
%$ dd = dates(B1,B2,B3,B4);
%$
%$ % Check the results.
%$ t(1) = dyn_assert(dates(B1)<dates(B2),1);
%$ t(2) = dyn_assert(dates(B2)<dates(B1),0);
%$ t(3) = dyn_assert(dates(B2)<dates(B1),0);
%$ t(4) = dyn_assert(dd<dates(B5),ones(4,1));
%$ t(5) = dyn_assert(dates(B5)<dd,zeros(4,1));
%$ t(6) = dyn_assert(dates(B1)<dd,[0; ones(3,1)]);
%$ T = all(t);
%@eof:2