function varargout = logde(t,y,flag)
% LOGDE Logistic differential equation
% 
if nargin < 3
	flag = '';
end
%
switch flag
	case ''
		varargout{1} = f(t,y);
  case 'jacobian'
		varargout{1} = jacobian(t,y);
	otherwise
   error(['Unknown flag ''' flag '''.']);
end
% 
function dy = f(t,y)
  dy = y - y.^2;
%
function dfdy = jacobian(t,y)
  dfdy = 1 - 2*y;