testIdwt :: (Array U DIM1 Double, Array U DIM1 Double, Array U DIM1 Double)
        -> Assertion
testIdwt (ls, sig, expected) =
    expected @=~? idwtS ls sig
testIdwt :: (Array U DIM1 Double, Array U DIM1 Double, Array U DIM1 Double)
        -> Assertion
testIdwt (ls, sig, expected) =
    expected @=~? idwtS ls sig
testIdwt (ls, sig, expected) =
    expected @=~? idwtS ls sig