Encode r←[x]⊤y

If x is not provided, it defaults to the scalar 2.

If x is non-scalar, operates on vectors of x and scalars of y, the following recursive procedure is performed:

If x is scalar, operates on vectors of y, x must have magnitude greater than 1 and the following recursive procedure is performed:

with the difference that encoding 0 returns ⟨0⟩ instead of ⟨⟩.

If the results of each vector of y are of different sizes, they are padded with 0s.

Supports the tolerance extra argument for the comparisons; supports the backward extra argument which reverses the results.