function a = reallog(b)
%REALLOG Real logarithm.
%   REALLOG(X) requires X to have real, nonnegative elements.
%
%   See also REALPOW, REALSQRT.

% $Revision: 1.6 $  $Date: 1998/12/17 19:07:29 $
% Copyright (c) 1984-1998 by The MathWorks, Inc.


a = log(b);
if( any(any(imag(a))) ),
   error( 'Reallog produces complex result.' );
end
