/// <summary>
/// Finds a perpendicular vector to two given
/// TODO: So far only implemented for 3D vectors
/// </summary>
public static GenTensor <T> VectorCrossProduct(GenTensor <T> a,
GenTensor <T> b)
{
#if ALLOW_EXCEPTIONS
if (!a.IsVector || !b.IsVector)
{
throw new InvalidShapeException($"Both {nameof(a)} and {nameof(b)} should be vectors");
}
if (a.Shape[0] != b.Shape[0])
{
throw new InvalidShapeException($"Length of {nameof(a)} and {nameof(b)} should be equal");
}
if (a.Shape[0] != 3)
{
throw new NotImplementedException("Other than vectors of the length of 3 aren't supported for VectorCrossProduct yet");
}
#endif
return(GenTensor <T> .CreateVector(
ConstantsAndFunctions <T> .Subtract(
ConstantsAndFunctions <T> .Multiply(a[1], b[2]),
ConstantsAndFunctions <T> .Multiply(a[2], b[1])),
ConstantsAndFunctions <T> .Subtract(
ConstantsAndFunctions <T> .Multiply(a[2], b[0]),
ConstantsAndFunctions <T> .Multiply(a[0], b[2])),
ConstantsAndFunctions <T> .Subtract(
ConstantsAndFunctions <T> .Multiply(a[0], b[1]),
ConstantsAndFunctions <T> .Multiply(a[1], b[0]))
));
}
public static GenTensor <T> Concat(GenTensor <T> a, GenTensor <T> b)
{
#if ALLOW_EXCEPTIONS
if (a.Shape.SubShape(1, 0) != b.Shape.SubShape(1, 0))
{
throw new InvalidShapeException("Excluding the first dimension, all others should match");
}
#endif
if (a.IsVector)
{
var resultingVector = GenTensor <T> .CreateVector(a.Shape.shape[0] + b.Shape.shape[0]);
for (int i = 0; i < a.Shape.shape[0]; i++)
{
resultingVector.SetValueNoCheck(ConstantsAndFunctions <T> .Forward(a.GetValueNoCheck(i)), i);
}
for (int i = 0; i < b.Shape.shape[0]; i++)
{
resultingVector.SetValueNoCheck(ConstantsAndFunctions <T> .Forward(b.GetValueNoCheck(i)), i + a.Shape.shape[0]);
}
return(resultingVector);
}
else
{
var newShape = a.Shape.Copy();
newShape.shape[0] = a.Shape.shape[0] + b.Shape.shape[0];
var res = new GenTensor <T>(newShape);
for (int i = 0; i < a.Shape.shape[0]; i++)
{
res.SetSubtensor(a.GetSubtensor(i), i);
}
for (int i = 0; i < b.Shape.shape[0]; i++)
{
res.SetSubtensor(b.GetSubtensor(i), i + a.Shape.shape[0]);
}
return(res);
}
}
