def sentence_ter_one_ref()

in vizseq/scorers/_ter.py [0:0]

• 12 lines of code
• 3 McCabe index (conditional complexity)

def sentence_ter_one_ref(hypothesis: str, reference: str) -> float:
    hypo_tokens, ref_tokens = hypothesis.split(), reference.split()
    n_shifts = 0
    prev_n_edits = get_edit_distance(hypo_tokens, ref_tokens)
    while True:
        new_n_edits, new_tokens = _shift(hypo_tokens, ref_tokens)
        if prev_n_edits - new_n_edits <= 0:
            break
        n_shifts += 1
        prev_n_edits = new_n_edits
        hypo_tokens = new_tokens
    return (n_shifts + prev_n_edits) / len(ref_tokens)