function [ U, V, P ] = uvp_stokes1 ( X, Y )

%*****************************************************************************80
%
%% uvp_stokes1() evaluates the exact Stokes solution #1.
%
%  Discussion:
%
%    The solution is defined over the unit square [0,1]x[0,1].
%
%  Licensing:
%
%    This code is distributed under the MIT license.
%
%  Modified:
%
%    16 June 2020
%
%  Author:
%
%    John Burkardt
%
%  Reference:
%
%    Junping Wang, Yanqiu Wang, Xiu Ye,
%    A robust numerical method for Stokes equations based on divergence-free
%    H(div) finite element methods,
%    SIAM Journal on Scientific Computing,
%    Volume 31, Number 4, 2009, pages 2784-2802.
%
%  Input:
%
%    real X, Y, the coordinates of the points.
%
%  Output:
%
%    real U, V, P, the velocity components and
%    pressure at each of the points.
%
  U = - 2.0 * X.^2 .* ( X - 1.0 ).^2 .* Y .* ( Y - 1.0 ) .* ( 2.0 * Y - 1.0 );

  V =   2.0 * Y.^2 .* ( Y - 1.0 ).^2 .* X .* ( X - 1.0 ) .* ( 2.0 * X - 1.0 );

  P = zeros ( size ( X ) );

  return
end
