/// <inheritdoc/>
public override ExpNode Execute(VectorProductOperNode node)
{
// Verify left and right child are two multiplyable vectors.
if (node.LeftChild is TensorNode vector1 && vector1.DimensionCount == 1 &&
node.RightChild is TensorNode vector2 && vector2.DimensionCount == 1 &&
vector1.SizeIdentity == vector2.SizeIdentity)
{
int size = vector1.GetDimensionSize(1);
switch (node.ProductMethod)
{
case VectorProductMethod.DOT:
ExpNode[] terms = new ExpNode[size];
for (int i = 0; i < size; i++)
{
terms[i] = QuickOpers.Multiply(vector1.GetChild(i), vector2.GetChild(i));
}
return(QuickOpers.Sum(terms).Execute(this));
case VectorProductMethod.CROSS: // TODO: Convert to matrix notation for determinant
default:
return(node);
}
}
return(HandleError(new CannotMultiplyTensors(this, node)));
}
/// <inheritdoc/>
public override ExpNode Execute(VarValueNode node)
{
if (node.Character != _variable.Character)
{
return(ConstantRule(node));
}
return(QuickOpers.Multiply(.5, QuickOpers.Pow(node, 2)));
}
/// <summary>
/// Multiplies a tensor by scalars.
/// </summary>
/// <param name="node">The <see cref="MultiplicationOperNode"/> to simplify.</param>
/// <param name="simplifier">The <see cref="Simplifier"/> calling.</param>
/// <returns>The resuling <see cref="MultiplicationOperNode"/>.</returns>
public static MultiplicationOperNode MultiplyScalarTensor(MultiplicationOperNode node, Simplifier simplifier)
{
TensorNode tensor1 = null;
int ti = -1;
for (int i = 0; i < node.ChildCount; i++)
{
if (i == ti)
{
continue;
}
if (node.GetChild(i) is TensorNode tensor2)
{
if (tensor1 != null)
{
if (i < ti)
{
TensorNode swap = tensor1;
tensor1 = tensor2;
tensor2 = swap;
}
if (!tensor1.CanMatrixMultiply(tensor2))
{
return((MultiplicationOperNode)simplifier.HandleError(new CannotMultiplyTensors(simplifier, node, $"Tensor nodes of size {tensor1.SizeIdentity} and {tensor2.SizeIdentity} could not be multiplied.")));
}
}
else
{
tensor1 = tensor2;
ti = i;
i = -1;
}
}
else
{
if (tensor1 != null)
{
for (int j = 0; j < tensor1.ChildCount; j++)
{
ExpNode simpleChild = QuickOpers.Multiply(tensor1.GetChild(j), node.GetChild(i)).Execute(simplifier);
tensor1.ReplaceChild(simpleChild, j);
}
node.RemoveChild(i);
if (i < ti)
{
ti--;
}
i--;
}
}
}
return(node);
}
/// <inheritdoc/>
public override ExpNode Execute(VectorProjOperNode node)
{
if (node.LeftChild.AreEqualSizeVectors(node.RightChild, out TensorNode a, out TensorNode b))
{
VectorProductOperNode adotb = QuickOpers.DotProduct(a, (TensorNode)b.Clone());
BOperNode bdotb = QuickOpers.DotProduct((TensorNode)b.Clone(), (TensorNode)b.Clone());
return(QuickOpers.Multiply(b, adotb, QuickOpers.Reciprical(bdotb)).Execute(this));
}
return(HandleError(new CannotVectorProject(this, node)));
}
/// <inheritdoc/>
public override ExpNode Execute(PowOperNode node)
{
// TODO: Handle variable in exponent
if (node.IsConstantBy(_variable))
{
return(QuickOpers.MakeNumericalNode(0));
}
var coefficient = node.RightChild;
var @base = node.LeftChild;
var exponent = QuickOpers.Add(-1, coefficient);
return(QuickOpers.Multiply(coefficient, QuickOpers.Pow(@base, exponent)));
}
/// <inheritdoc/>
public override ExpNode Execute(SineOperNode node)
{
if (node.IsConstantBy(_variable))
{
return(QuickOpers.MakeNumericalNode(0));
}
// Apply chain rule
var coefficient = node.Child.Clone().Execute(this);
// Apply table
var sinFunc = SineTable(node);
return(QuickOpers.Multiply(coefficient, sinFunc));
}
/// <inheritdoc/>
public override ExpNode Execute(SineOperNode node)
{
if (node.IsConstantBy(_variable))
{
return(ConstantRule(node));
}
Differentiator diff = new(_variable);
// Apply ChainRule
var coefficient = node.Child.Execute(diff);
// Apply table
var sinFunc = SineTable(node);
return(QuickOpers.Multiply(QuickOpers.Reciprical(coefficient), sinFunc));
}
/// <inheritdoc/>
public override ExpNode Execute(PowOperNode node)
{
// TODO: Handle variable in exponent
if (node.IsConstantBy(_variable))
{
return(ConstantRule(node));
}
// Increment exponent, divide by exponent
AdditionOperNode exponent = QuickOpers.Add(1, node.RightChild);
RecipricalOperNode coefficient = QuickOpers.Reciprical(exponent.Clone());
PowOperNode @base = QuickOpers.Pow(node.LeftChild, exponent);
return(QuickOpers.Multiply(coefficient, @base));
}
/// <inheritdoc/>
public override ExpNode Execute(SignOperNode node)
{
node.Child = node.Child.Execute(this);
switch (node.Sign)
{
case Sign.POSITIVE:
return(node.Child);
case Sign.NEGATIVE:
{
if (node.Child is NumericalValueNode nvNode)
{
return(QuickOpers.MakeNumericalNode(nvNode.DoubleValue * -1));
}
return(QuickOpers.Multiply(-1, node.Child).Execute(this));
}
default:
return(node);
}
}
