def api_answer_question(user_id, question_id, answer):
"""
提交对应问题的回答。
参数：
user_id 提交回答的用户的 ID；
question_id 要回答的问题的 ID；
answer 用户的回答。
"""
p_validate_argument('user_id', user_id, int, 'question_id', question_id, int, 'answer', answer, str)
questions = Question.objects.filter(id = question_id)
if len(questions) != 1:
raise APIException('不存在的问题。')
question = questions[0]
if question.user_id != user_id:
raise APIException('该问题不属于此用户。')
if question.answered:
raise APIException('该问题已经被回答。')
with transaction.atomic():
question.answered = True
question.answer_date = timezone.now()
question.answer_is_correct = True if question.correct_answer == answer else False
question.save()
learned_words = LearnedWord.objects.filter(word_id = question.related_word_id, user_id = user_id)
if len(learned_words) == 0:
learned_word = LearnedWord(word_id = question.related_word_id, user_id = user_id)
learned_word.save()
else:
learned_word = learned_words[0]
learned_word.last_review_date = timezone.now().date()
learned_word.unfamiliarity = p_calculate_unfamiliarity(learned_word)
learned_word.total_answered_count += 1
if question.answer_is_correct:
learned_word.correct_answered_count += 1
learned_word.unfamiliarity -= 1 / UNFAMILIARITY_COEFFICIENT
else:
learned_word.unfamiliarity += 1 / UNFAMILIARITY_COEFFICIENT
learned_word.unfamiliarity = p_bound_value(learned_word.unfamiliarity, (0, 1))
learned_word.save()
return question.correct_answer
def p_recheck_leanred_words(user):
"""
重新检查并计算给定用户的已学习生词的信息。
参数：
待重新检查的用户的 ID。
"""
with transaction.atomic():
LearnedWord.objects.all().delete()
question_dict = {}
for question in Question.objects.filter(user_id = user.id, answered = True):
if question.related_word_id not in question_dict:
question_dict[question.related_word_id] = []
question_dict[question.related_word_id].append(question)
for key, value in question_dict.items():
learned_word = LearnedWord(word_id = key, user_id = user.id)
learned_word.save()
value.sort(key = lambda q: q.answer_date)
unfamiliarity = 1
learned_word.learned_date = current_date = value[0].answer_date.date()
total_answered_count = 0
correct_answered_count = 0
for question in value:
time_delta = question.answer_date.date() - current_date
unfamiliarity = p_calculate_unfamiliarity_with_params(time_delta, unfamiliarity, correct_answered_count)
total_answered_count += 1
if question.answer_is_correct:
correct_answered_count += 1
unfamiliarity -= 1 / UNFAMILIARITY_COEFFICIENT
else:
unfamiliarity += 1 / UNFAMILIARITY_COEFFICIENT
unfamiliarity = p_bound_value(unfamiliarity, (0, 1))
current_date = question.answer_date.date()
learned_word.last_review_date = current_date
learned_word.total_answered_count = total_answered_count
learned_word.correct_answered_count = correct_answered_count
learned_word.unfamiliarity = unfamiliarity
learned_word.save()