/// <summary>
/// \/ * value operation is called gradient
/// gradient over scalar field generate a vector
/// </summary>
/// <param name="value"></param>
/// <returns></returns>
public override QsValue MultiplyOperation(QsValue value)
{
var fscalar = value as QsScalar;
if (!Object.ReferenceEquals(fscalar, null))
{
// Here we will multiply the nabla \/ * with @function
if (!Object.ReferenceEquals(fscalar.FunctionQuantity, null))
{
var f = fscalar.FunctionQuantity.Value;
string[] prms = f.ParametersNames;
SymbolicVariable fsv = f.ToSymbolicVariable();
QsVector GradientResult = new QsVector();
// we loop through the symbolic body and differentiate it with respect to the function parameters.
// then accumulate the
foreach (string prm in prms)
{
GradientResult.AddComponent(fsv.Differentiate(prm).ToQuantity().ToScalar());
}
return(GradientResult);
}
}
if (value is QsVector)
{
return(this.DelVector.MultiplyVector((QsVector)value));
}
throw new NotImplementedException(@"Multiplication of \/ * " + value.GetType().Name + " Not implemented yet");
}
/// <summary>
/// Differentiate operation for function.
/// </summary>
/// <param name="value">object of <see cref="QsScalar"/> that hold <see cref="AnyQuantity<SymbolicVariable>"/></param>
/// <returns></returns>
public override QsValue DifferentiateOperation(QsValue value)
{
QsScalar sval = (QsScalar)value;
if (sval.ScalarType == ScalarTypes.SymbolicQuantity)
{
var dsv = sval.SymbolicQuantity.Value;
string fname = "_";
string WholeFunction = string.Empty;
if (this.FunctionBodyToken[0].TokenClassType == typeof(CurlyBracketGroupToken))
{
// vector differentiation
// take every term in the vector and differentiate it
var vcs = QsVar.VectorComponents(this.FunctionBodyToken[0]);
StringBuilder sc = new StringBuilder();
sc.Append(fname + "(" + RemoveRedundantParameters(this.ParametersNames) + ") = ");
sc.Append("{ ");
foreach (var c in vcs)
{
SymbolicVariable nsv = SymbolicVariable.Parse(c);
int times = (int)dsv.SymbolPower;
while (times > 0)
{
nsv = nsv.Differentiate(dsv.Symbol);
times--;
}
sc.Append(nsv.ToString());
sc.Append(" ");
}
sc.Append("}");
WholeFunction = sc.ToString();
}
else
{
SymbolicVariable nsv = ToSymbolicVariable();
int times = (int)dsv.SymbolPower;
while (times > 0)
{
nsv = nsv.Differentiate(dsv.Symbol);
times--;
}
WholeFunction = fname + "(" + RemoveRedundantParameters(this.ParametersNames) + ") = " + nsv.ToString();
}
return(QsFunction.ParseFunction(QsEvaluator.CurrentEvaluator, WholeFunction));
}
else
{
return(base.DifferentiateOperation(value));
}
}
