function value = year_is_leap_julian ( y ) %*****************************************************************************80 % %% YEAR_IS_LEAP_JULIAN returns TRUE if the Julian year was a leap year. % % Algorithm: % % If ( Y < 0 and Y+1 is divisible by 4 ) then % the year is a leap year. % else if ( Y == 0 ) then % the year is illegal % else if ( 0 < Y and Y is divisible by 4 ) then % the year is a leap year. % else % the year is NOT a leap year. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 19 June 2012 % % Author: % % John Burkardt % % Parameters: % % Input, integer Y, the year to be checked. % % Output, logical VALUE, TRUE if the year was a leap year, % FALSE otherwise. % if ( y == 0 ) value = 0; return end y2 = y_common_to_astronomical ( y ); if ( i4_modp ( y2, 4 ) == 0 ) year_is_leap_julian = 1; else year_is_leap_julian = 0; end return end