function fjac = p00_jac ( problem, n, x )

%*****************************************************************************80
%
%% P00_JAC evaluates the jacobian for any problem.
%
%  Discussion:
%
%    P00_JAC evaluates the matrix FJAC(I,J)  =  D F(I) / D X(J)
%    given the problem chosen, the number of equations, and the value
%    of the point X.
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    10 October 2020
%
%  Author:
%
%    John Burkardt
%
%  Input:
%
%    integer PROBLEM, the problem number.
%
%    integer N, the number of variables and equations.
%
%    real X(N), the evaluation point.
%
%  Output:
%
%    real FJAC(N,N), the jacobian matrix.
%
  if ( problem == 1 )
    fjac = p01_jac ( n, x );
  elseif ( problem == 2 )
    fjac = p02_jac ( n, x );
  elseif ( problem  ==  3 )
    fjac = p03_jac ( n, x );
  elseif ( problem == 4 )
    fjac = p04_jac ( n, x );
  elseif ( problem == 5 )
    fjac = p05_jac ( n, x );
  elseif ( problem == 6 )
    fjac = p06_jac ( n, x );
  elseif ( problem == 7 )
    fjac = p07_jac ( n, x );
  elseif ( problem == 8 )
    fjac = p08_jac ( n, x );
  elseif ( problem == 9 )
    fjac = p09_jac ( n, x );
  elseif ( problem == 10 )
    fjac = p10_jac ( n, x );
  elseif ( problem == 11 )
    fjac = p11_jac ( n, x );
  elseif ( problem == 12 )
    fjac = p12_jac ( n, x );
  elseif ( problem == 13 )
    fjac = p13_jac ( n, x );
  elseif ( problem == 14 )
    fjac = p14_jac ( n, x );
  elseif ( problem == 15 )
    fjac = p15_jac ( n, x );
  elseif ( problem == 16 )
    fjac = p16_jac ( n, x );
  elseif ( problem == 17 )
    fjac = p17_jac ( n, x );
  elseif ( problem == 18 )
    fjac = p18_jac ( n, x );
  elseif ( problem == 19 )
    fjac = p19_jac ( n, x );
  elseif ( problem == 20 )
    fjac = p20_jac ( n, x );
  elseif ( problem == 21 )
    fjac = p21_jac ( n, x );
  elseif ( problem == 22 )
    fjac = p22_jac ( n, x );
  elseif ( problem == 23 )
    fjac = p23_jac ( n, x );
  else
    fprintf ( 1, '\n' );
    fprintf ( 1, 'P00_JAC - Fatal error!\n' );
    fprintf ( 1, '  Illegal problem number = %d\n', problem );
    error ( 'P00_JAC - Fatal error!' );
  end

  return
end
