/// <summary>
/// Creates a Tensor from an Abstraction.
/// The difference with Elementwise.Create is that we reuse the existing arrays.
/// </summary>
private Tensor <Type> Lift(Scalar <Type> expr)
{
if (expr == this.Abstraction)
{
return(this);
}
var result = Vars.FirstOrDefault(e => e == expr);
if (result != null)
{
return(Inputs[Array.IndexOf(Vars, expr)]);
}
// HACK: here the `Clone` only works on some specific cases.
switch (expr)
{
case Scalar <Type> .Binary binary:
return(Op.Apply(Lift(binary.x), Lift(binary.y), (_x, _y) => binary.Clone(_x, _y)));
case Scalar <Type> .Unary unary:
return(Op.Apply(Lift(unary.x), _x => unary.Clone(_x)));
case Scalar <Type> .Const cst:
return(Op.ConstLike(expr, this));
default:
throw new NotImplementedException();
}
}
internal static Tensor <Type> Create(Tensor <Type> x, Func <Scalar <Type>, Scalar <Type> > f)
{
if (x is Fill <Type> )
{
var fill = (Fill <Type>)x;
return(Op.ConstLike(f(fill.x), fill));
}
else
{
var _x = new Scalar <Type> .Var($"_x{x0++}");
return(Create(new[] { x }, new[] { _x }, f(_x)));
}
}
