def band.step
import emerging-ezaudio@0.4.0.0/src/mp3_enc.bend as Mp3Encimport Base
905def band.step(
906 hop: Nat, +vec: List<&2, F32>, got: Bf, +kk: U32, acc: List<&2, F32>
907) -> Array<F32> & List<&2, F32>:
908 match hop got:
909 case 0n Bf{tab, co}:
910 (tab, f.rev((co <> acc)))
911 case 1n+p Bf{tab, co}:
912 band.step(p, vec, bf.of(bt.dot(vec, tab, ((kk + 1 : U32) * 36 : U32), 0.0)), (kk + 1 : U32),
913 (co <> acc))