compute_H_and_inverse()

The constant H is an artifact of the computation \( B = 1 \) for log arithmetic. We use H when scaling down by the radix and ONE_OVER_H when scaling up. This simple routine substitutes \( 2 \) for the radix, when the radix is less than \( 1 \).

def compute_H_and_inverse():
    """Return min(1/B, 1/2) and reciprocal, noting H is a fraction."""
    if B < TWO:
        h_inv = TWO
    else:
        h_inv = B
    return ONE / h_inv, h_inv