function a = complex_i_matrix ( )

%*****************************************************************************80
%
%% complex_i_matrix returns the COMPLEX_I matrix.
%
%  Formula:
%
%    0 1
%   -1 0
%
%  Properties:
%
%    A is integral: int ( A ) = A.
%
%    A is anti-involutional: A * A = - I
%
%    A * A * A * A = I
%
%    A is not diagonally dominant.
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    01 October 2007
%
%  Author:
%
%    John Burkardt
%
%  Output:
%
%    real A(2,2), the matrix.
%
  a = [ 0.0, 1.0; ...
       -1.0, 0.0 ];

  return
end
