/// <summary>
/// Adds tensors.
/// </summary>
/// <param name="node">The <see cref="AdditionOperNode"/> containing tensors.</param>
/// <param name="simplifier">The <see cref="Simplifier"/> calling.</param>
/// <returns>The resuling <see cref="ExpNode"/>.</returns>
public static ExpNode SumTensors(AdditionOperNode node, Simplifier simplifier)
{
if (node.GetChild(0) is TensorNode tensorNode)
{
for (int i = 1; i < node.ChildCount; i++)
{
if (node.GetChild(i) is TensorNode otherTensorNode)
{
if (otherTensorNode.SizeIdentity == tensorNode.SizeIdentity)
{
for (int j = 0; j < tensorNode.ChildCount; j++)
{
ExpNode addedNode = QuickOpers
.Sum(tensorNode.GetChild(j), otherTensorNode.GetChild(j))
.Execute(simplifier);
tensorNode.ReplaceChild(addedNode, j);
}
}
else
{
return(simplifier.HandleError(new CannotAddTensors(simplifier, node, $"Cannot add tensor of shape {otherTensorNode.SizeIdentity} and tensor of shape {tensorNode.SizeIdentity}.")));
}
}
else
{
return(simplifier.HandleError(new CannotAddTensors(simplifier, node, "Cannot add scalar and tensor.")));
}
}
return(tensorNode);
}
else
{
// There is a scalar.
// There cannot be any tensors
for (int i = 1; i < node.ChildCount; i++)
{
if (node.GetChild(i) is TensorNode)
{
return(simplifier.HandleError(new CannotAddTensors(simplifier, node, "Cannot add tensor and scalar.")));
}
}
}
return(node);
}
/// <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);
}
