/// <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(TensorNode node)
{
for (int i = 0; i < node.ChildCount; i++)
{
ExpNode simpleChild = node.GetChild(i).Execute(this);
node.ReplaceChild(simpleChild, i);
}
return(node);
}
/// <inheritdoc/>
public override string Print(TensorNode node)
{
string cache = string.Empty;
switch (node.TensorType)
{
case TensorType.Vector:
{
// Print each child seperated by ',' wrapped in "<>";
cache += "<";
for (int i = 0; i < node.ChildCount; i++)
{
cache += node.GetChild(i).Print(this);
if (i < node.ChildCount - 1)
{
cache += ",";
}
}
cache += ">";
return(cache);
}
case TensorType.Matrix:
{
cache = $"\\matrix{node.SizeIdentity}{{";
for (int i = 0; i < node.ChildCount; i++)
{
cache += node.GetChild(i).Print(this);
if (i < node.ChildCount - 1)
{
cache += ",";
}
}
cache += "}";
return(cache);
}
default:
// TODO: Print matricies and tensors
return(string.Empty);
}
}
