function resultFlag = IsOctave
% resultFlag = IsOctave
%
% Returns true if the script is running under GNU/Octave.
%
% Some scripts need to behave differently when running under
% GNU/Octave instead of running under Mathworks Matlab.

% History:
% 05/10/06 Written (MK).
% 03/08/06 Added the 'var' parameter to the exist function to make it
%          faster.  On my box it cuts 4+ ms off this function call. (CGB)
% 18/09/06 'var' parameter was wrong! It is a 'builtin' parameter (MK).
% 18/06/09 Add persistent rc caching to speed it up (MK).

persistent rc;

if isempty(rc)
	% If the built-in variable OCTAVE_VERSION exists,
	% then we are running under GNU/Octave, otherwise not.
	if ismember(exist('OCTAVE_VERSION', 'builtin'), [102, 5])
	  rc = 1;
	else
	  rc = 0;
	end;
end

resultFlag = rc;
return;