public static Tensor <Type> Create(Tensor <Type> x, IReadOnlyList <XSlice> slices)
{
if (slices.Count == 0)
{
throw new RankException("no slices provided");
}
if (x is BroadCast <Type> xBroad) // && slices.Count == 1 && slices[0].IsSingleton()
{
var broadcasted = xBroad.broadcast;
var needBroadcast = new List <int>();
var keptSlices = new List <XSlice>();
for (int d = 0; d < slices.Count; ++d)
{
if (broadcasted.Contains(d))
{
if (slices[d].IsSingleton)
{
keptSlices.Add(0);
}
else
{
keptSlices.Add(XSlicer._);
needBroadcast.Add(d);
}
}
else
{
keptSlices.Add(slices[d]);
}
}
if (needBroadcast.Count == 0)
{
return(xBroad.x[keptSlices]);
}
else
{
return(new Slicing <Type>(x, slices.ToArray()));
}
}
var result = new Slicing <Type>(x, slices.ToArray());
switch (x)
{
case Fill <Type> fill:
return(Op.ConstLike(fill.x, result));
default:
return(result);
}
}
/// <summary>Advanced indexing</summary>
/// <remarks>`indices.Length` should match `x.NDim`</remarks>
/// <param name="x">the array to index</param>
/// <param name="indices">the indices to take from `x`.</param>
public static Tensor <Type> Create(Tensor <Type> x, Tensor <int>[] indices)
{
var result = new Indexing <Type>(x, indices);
switch (x)
{
case Fill <Type> fill:
return(Op.ConstLike(fill.x, result));
default:
return(result);
}
}
static public Tensor <Type> Create(Tensor <Type> x, int axis)
{
axis = axis < 0 ? axis + x.NDim : axis;
var result = new Sum <Type>(x, axis);
switch (x)
{
case Fill <Type> fill:
return(Op.ConstLike(fill.x * x.Shape[axis].As <Type>(), result));
case OneHot <Type> oneHot:
return(axis == 0 ? oneHot.Content.Reshape(result.Shape) : result);
case OneHotPoint <Type> oneHotPoint:
var point = ((Scalar <int>[])oneHotPoint.Indexes).ToArray();
point[axis] = 0;
return(Op.OneHot(result.Shape, point, oneHotPoint.Content));
default:
return(result);
}
}