/// <summary>
/// Calculates the DG-projection (with respect to the DG-basis
/// of this field, <see cref="Basis"/>) of
/// <paramref name="alpha"/>*<paramref name="a"/>*<paramref name="b"/>
/// and, depending on the value of <paramref name="accumulateResult"/>,
/// either adds or assigns it to this field.
/// </summary>
/// <param name="a">1st multiplicand</param>
/// <param name="b">2nd multiplicand</param>
/// <param name="alpha">scaling for <paramref name="a"/>*<paramref name="b"/></param>
/// <param name="em">
/// An optional restriction to the domain in which the projection is
/// computed (it may, e.g. be only required in boundary cells, so a
/// computation over the whole domain would be a waste of computational
/// power. A proper execution mask would be see e.g.
/// <see cref="GridData.BoundaryCells"/>.)<br/>
/// if null, the computation is carried out in the whole domain;
/// </param>
/// <param name="accumulateResult">
/// Tells this method whether to accumulate (true) or not (false)
/// </param>
virtual public void ProjectProduct(double alpha, DGField a, DGField b, CellMask em, bool accumulateResult)
{
if (!object.ReferenceEquals(a.Basis.GridDat, this.Basis.GridDat))
{
throw new ArgumentException("field is associated to another grid.", "a");
}
if (!object.ReferenceEquals(b.Basis.GridDat, this.Basis.GridDat))
{
throw new ArgumentException("field is associated to another grid.", "b");
}
if (!accumulateResult)
{
if (a == this)
{
a = (DGField)a.Clone();
if (b == this)
{
b = a;
}
}
else if (b == this)
{
b = (DGField)b.Clone();
}
this.Clear();
}
SpatialOperator multOp = new SpatialOperator(new string[] { "a", "b" },
new string[] { "res" },
QuadOrderFunc.NonLinear(2));
multOp.EdgeQuadraturSchemeProvider = g => new EdgeQuadratureScheme(true, EdgeMask.GetEmptyMask(g));
multOp.VolumeQuadraturSchemeProvider = g => new CellQuadratureScheme(true, em);
multOp.EquationComponents["res"].Add(new MultiplySource());
multOp.Commit();
var ev = multOp.GetEvaluatorEx(
new[] { a, b }, null, this.Mapping);
ev.Evaluate <CoordinateVector>(alpha, 1.0, this.CoordinateVector);
}
/// <summary>
/// accumulates
/// <paramref name="alpha"/>*<paramref name="f"/>(<paramref name="U"/>)
/// to this field;
/// </summary>
/// <param name="alpha">scaling</param>
/// <param name="f">
/// some function
/// - 1st argument: position in physical space
/// - 2nd argument: values of fields in <paramref name="U"/> at respective position
/// - 3rd argument: cell index
/// - return value: value of function that should be projected at the respective position
/// </param>
/// <param name="cqs">
/// cell quadrature scheme: domain and quadrature rule
/// </param>
/// <param name="U">
/// arguments for <paramref name="f"/>
/// </param>
public void ProjectFunction(double alpha, Func <Vector, double[], int, double> f, CellQuadratureScheme cqs, params DGField[] U)
{
string[] Dom = new string[U.Length];
for (int i = 0; i < Dom.Length; i++)
{
Dom[i] = "_" + i;
}
string[] Cod = new string[] { "res" };
SpatialOperator src = new SpatialOperator(Dom, Cod, QuadOrderFunc.NonLinear(3));
src.EquationComponents[Cod[0]].Add(new ProjectFunctionSource(Dom, f));
src.EdgeQuadraturSchemeProvider = g => new EdgeQuadratureScheme(false, EdgeMask.GetEmptyMask(this.Basis.GridDat));
src.VolumeQuadraturSchemeProvider = g => cqs;
src.Commit();
var ev = src.GetEvaluatorEx(
new CoordinateMapping(U), null, this.Mapping);
ev.Evaluate(alpha, 1.0, this.CoordinateVector);
}
/// <summary>
/// creates the spatial operator that consists only of component <paramref name="c"/>
/// </summary>
public static SpatialOperator Operator(this IEquationComponent c, int DegreeOfNonlinearity = 1)
{
return(Operator(c, QuadOrderFunc.NonLinear(DegreeOfNonlinearity)));
}
/// <summary>
/// creates the spatial operator that consists only of component <paramref name="c"/>
/// </summary>
public static SpatialOperator Operator(this IEquationComponent c, int DegreeOfNonlinearity = 1, Func <IGridData, EdgeQuadratureScheme> edgeSchemeProvider = null, Func <IGridData, CellQuadratureScheme> cellSchemeProvider = null)
{
return(Operator(c, QuadOrderFunc.NonLinear(DegreeOfNonlinearity), edgeSchemeProvider, cellSchemeProvider));
}
