private static void Main(string[] args)
//****************************************************************************80
//
// Purpose:
//
// MAIN is the main program for WEDGE_EXACTNESS.
//
// Discussion:
//
// This program investigates the polynomial exactness of a quadrature
// rule for the unit wedge.
//
// The interior of the unit wedge in 3D is defined by the constraints:
// 0 <= X
// 0 <= Y
// X + Y <= 1
// -1 <= Z <= +1
//
// Licensing:
//
// This code is distributed under the GNU LGPL license.
//
// Modified:
//
// 24 August 2014
//
// Author:
//
// John Burkardt
//
{
int degree;
int degree_max;
string quad_filename;
Console.WriteLine("");
Console.WriteLine("WEDGE_EXACTNESS");
Console.WriteLine(" Investigate the polynomial exactness of a quadrature");
Console.WriteLine(" rule for the unit wedge.");
//
// Get the quadrature file root name:
//
try
{
quad_filename = args[0];
}
catch
{
Console.WriteLine("");
Console.WriteLine("WEDGE_EXACTNESS:");
Console.WriteLine(" Enter the \"root\" name of the quadrature files.");
quad_filename = Console.ReadLine();
}
//
// Create the names of:
// the quadrature X file;
// the quadrature W file;
//
string quad_w_filename = quad_filename + "_w.txt";
string quad_x_filename = quad_filename + "_x.txt";
//
// The second command line argument is the maximum degree.
//
try
{
degree_max = Convert.ToInt32(args[1]);
}
catch
{
Console.WriteLine("");
Console.WriteLine("WEDGE_EXACTNESS:");
Console.WriteLine(" Please enter the maximum total degree to check.");
degree_max = Convert.ToInt32(Console.ReadLine());
}
//
// Summarize the input.
//
Console.WriteLine("");
Console.WriteLine("WEDGE_EXACTNESS: User input:");
Console.WriteLine(" Quadrature rule X file = \"" + quad_x_filename + "\".");
Console.WriteLine(" Quadrature rule W file = \"" + quad_w_filename + "\".");
Console.WriteLine(" Maximum total degree to check = " + degree_max + "");
//
// Read the X file.
//
TableHeader hd = typeMethods.r8mat_header_read(quad_x_filename);
int dim_num = hd.m;
int order = hd.n;
Console.WriteLine("");
Console.WriteLine(" Spatial dimension = " + dim_num + "");
Console.WriteLine(" Number of points = " + order + "");
if (dim_num != 3)
{
Console.WriteLine("");
Console.WriteLine("WEDGE_EXACTNESS - Fatal error!");
Console.WriteLine(" The quadrature abscissas must be 3 dimensional.");
return;
}
double[] x = typeMethods.r8mat_data_read(quad_x_filename, dim_num, order);
//
// Read the W file.
//
hd = typeMethods.r8mat_header_read(quad_w_filename);
int dim_num2 = hd.m;
int order2 = hd.n;
if (dim_num2 != 1)
{
Console.WriteLine("");
Console.WriteLine("WEDGE_EXACTNESS - Fatal error!");
Console.WriteLine(" The quadrature weight file should have exactly");
Console.WriteLine(" one value on each line.");
return;
}
if (order2 != order)
{
Console.WriteLine("");
Console.WriteLine("WEDGE_EXACTNESS - Fatal error!");
Console.WriteLine(" The quadrature weight file should have exactly");
Console.WriteLine(" the same number of lines as the abscissa file.");
return;
}
double[] w = typeMethods.r8mat_data_read(quad_w_filename, 1, order);
//
// Explore the monomials.
//
int[] expon = new int[dim_num];
Console.WriteLine("");
Console.WriteLine(" Error Degree Exponents");
Console.WriteLine("");
for (degree = 0; degree <= degree_max; degree++)
{
bool more = false;
int h = 0;
int t = 0;
for (;;)
{
Comp.comp_next(degree, dim_num, ref expon, ref more, ref h, ref t);
double[] v = Monomial.monomial_value(dim_num, order, expon, x);
double quad = Integrals.wedge01_volume() * typeMethods.r8vec_dot_product(order, w, v);
double exact = Integrals.wedge01_integral(expon);
double quad_error = Math.Abs(quad - exact);
string cout = " " + quad_error.ToString(CultureInfo.InvariantCulture).PadLeft(12)
+ " " + degree.ToString().PadLeft(2)
+ " ";
int dim;
for (dim = 0; dim < dim_num; dim++)
{
cout += expon[dim].ToString().PadLeft(3);
}
Console.WriteLine(cout);
if (!more)
{
break;
}
}
Console.WriteLine("");
}
Console.WriteLine("");
Console.WriteLine("WEDGE_EXACTNESS:");
Console.WriteLine(" Normal end of execution.");
Console.WriteLine("");
}
