private static void test02()
//****************************************************************************80
//
// Purpose:
//
// TEST02 checks the basis functions.
//
// Licensing:
//
// This code is distributed under the GNU LGPL license.
//
// Modified:
//
// 07 July 2014
//
// Author:
//
// John Burkardt
//
{
int i;
double xq;
double[] xx =
{
2.0, 1.0, 0.0, 0.0, 0.0, 1.0, 2.0, 2.0
}
;
double yq;
double[] yy =
{
5.0, 5.0, 5.0, 4.0, 3.0, 3.0, 3.0, 4.0
}
;
Console.WriteLine("");
Console.WriteLine("TEST02");
Console.WriteLine(" Basis function checks.");
//
// Check that V is identity matrix at nodes.
//
Console.WriteLine("");
Console.WriteLine(" The matrix Aij = V(j)(X(i),Y(i)) should be the identity.");
Console.WriteLine("");
double xw = 0.0;
double ys = 3.0;
double xe = 2.0;
double yn = 5.0;
for (i = 0; i < 8; i++)
{
xq = xx[i];
yq = yy[i];
FEM_2D_BVP_Serene.basis_serene(xq, yq, xw, ys, xe, yn, xx, yy);
int j;
for (j = 0; j < 8; j++)
{
}
Console.WriteLine("");
}
//
// Check that VX and VY sum to zero anywhere.
//
Console.WriteLine("");
Console.WriteLine(" The vectors dVdX(1:8)(X,Y) and dVdY(1:8)(X,Y)");
Console.WriteLine(" should both sum to zero for any (X,Y).");
int seed = 123456789;
xq = 2.0 * UniformRNG.r8_uniform_01(ref seed);
yq = 3.0 + 2.0 * UniformRNG.r8_uniform_01(ref seed);
xw = 0.0;
ys = 3.0;
xe = 2.0;
yn = 5.0;
double[] vx = FEM_2D_BVP_Serene.basis_dx_serene(xq, yq, xw, ys, xe, yn, xx, yy);
double[] vy = FEM_2D_BVP_Serene.basis_dy_serene(xq, yq, xw, ys, xe, yn, xx, yy);
Console.WriteLine("");
Console.WriteLine(" Random evaluation point is (" + xq + "," + yq + ")");
Console.WriteLine("");
Console.WriteLine(" dVdX dVdY");
Console.WriteLine("");
for (i = 0; i < 8; i++)
{
Console.WriteLine(i.ToString(CultureInfo.InvariantCulture).PadLeft(6) + " "
+ vx[i].ToString(CultureInfo.InvariantCulture).PadLeft(10) + " "
+ vy[i].ToString(CultureInfo.InvariantCulture).PadLeft(10) + "");
}
Console.WriteLine("");
Console.WriteLine(" Sum: "
+ typeMethods.r8vec_sum(8, vx).ToString(CultureInfo.InvariantCulture).PadLeft(10) + " "
+ typeMethods.r8vec_sum(8, vy).ToString(CultureInfo.InvariantCulture).PadLeft(10) + "");
}
