Question

在这里，我有一个程序可以对学生进行测验并保存他们的分数，供老师查看。但是现在我被要求保存每个学生最后三个分数，这意味着该程序必须识别人名，我该怎么做？

import random
import sys

def get_input_or_quit(prompt, quit="Q"):
    prompt += " (Press '{}' to exit) : ".format(quit)
    val = input(prompt).strip()
    if val.upper() == quit:
        sys.exit("Goodbye")
    return val

def prompt_bool(prompt):
    while True:
        val = get_input_or_quit(prompt).lower()

        if val == 'yes':
          return True
        elif val == 'no':
          return False
        else:
         print ("Invalid input '{}', please try again".format(val))


def prompt_int_small(prompt='', choices=(1,2)):
    while True:
        val = get_input_or_quit(prompt)
        try:
            val = int(val)
            if choices and val not in choices:
                raise ValueError("{} is not in {}".format(val, choices))
            return val
        except (TypeError, ValueError) as e:
                print(
                    "Not a valid number ({}), please try again".format(e)
                    )

def prompt_int_big(prompt='', choices=(1,2,3)):
    while True:
        val = get_input_or_quit(prompt)
        try:
            val = int(val)
            if choices and val not in choices:
                raise ValueError("{} is not in {}".format(val, choices))
            return val
        except (TypeError, ValueError) as e:
                print(
                    "Not a valid number ({}), please try again".format(e)
                    )

role = prompt_int_small("Are you a teacher or student? Press 1 if you are a student or 2 if you are a teacher")
if role == 1:
    score=0
    name=input("What is your name?")
    print ("Alright",name,"welcome to your maths quiz."
            " Remember to round all answers to 5 decimal places.")
    level_of_difficulty = prompt_int_big("What level of difficulty are you working at?\n"
                                 "Press 1 for low, 2 for intermediate "
                                    "or 3 for high\n")


    if level_of_difficulty == 3:
        ops = ['+', '-', '*', '/']
    else:
        ops = ['+', '-', '*']

    for question_num in range(1, 11):
        if level_of_difficulty == 1:
            max_number = 10
        else:
            max_number = 20

        number_1 = random.randrange(1, max_number)
        number_2 = random.randrange(1, max_number)

        operation = random.choice(ops)

        maths = round(eval(str(number_1) + operation + str(number_2)),5)
        print('\nQuestion number: {}'.format(question_num))
        print ("The question is",number_1,operation,number_2)
        answer = float(input("What is your answer: "))
        if answer == maths:
            print("Correct")
            score = score + 1
        else:
            print ("Incorrect. The actual answer is",maths)

    if score >5:
        print("Well done you scored",score,"out of 10")
    else:
        print("Unfortunately you only scored",score,"out of 10. Better luck next time")


    class_number = prompt_int_big("Before your score is saved ,are you in class 1, 2 or 3? Press the matching number")

    filename = (str(class_number) + "txt")
    with open(filename, 'a') as f:
        f.write("\n" + str(name) + " scored " + str(score) +  " on difficulty level " + str(level_of_difficulty) + "\n")
    with open(filename) as f:
        lines = [line for line in f if line.strip()]
        lines.sort()

    if prompt_bool("Do you wish to view previous results for your class"):
        for line in lines:
            print (line)
    else:
        sys.exit("Thanks for taking part in the quiz, your teacher should discuss your score with you later")
if role == 2:
    class_number = prompt_int_big("Which class' scores would you like to see? Press 1 for class 1, 2 for class 2 or 3 for class 3")
    filename = (str(class_number) + "txt")

    f = open(filename, "r")
    lines = [line for line in f if line.strip()]
    lines.sort()
    for line in lines:
        print (line)

Answer 1

您可以使用字典。关键是学生姓名，价值可以是最后3个分数的列表。在测试结束时，您将更新字典，如下所示：

try:
     scoresDict[name][2] = score
except KeyError:
     scoresDict[name] = [None, None, score]

在上面的示例中，最新得分始终是列表中的最后得分。 scoresDict需要初始化为空字典（或从文件中读取 - 见下文）。您首先尝试将分数添加到现有name，如果失败，则在dict中创建一个新条目。

程序关闭后，您需要保留数据。您可以使用pickle模块执行此操作。

当程序启动时，您将尝试从文件加载现有数据，或者如果文件不存在则创建新的scoresDict：

scoresDict = {}
fpath = os.path.join(os.path.dirname(__file__), "scores.pickle")
if os.path.exists(fpath):
    with open(fpath, "r") as f:
        scoresDict = pickle.load(f)

当程序关闭时，在更新得分dict之后，将其转储回磁盘：

with open(fpath, "w") as f:
    pickle.dump(scoresDict, f)

这将非常适合简单的需求。对于更复杂的数据，或者如果您计划存储大量数据，则应该考虑使用数据库。 Python在其标准库中附带了一个SQLite模块，可以使用它。

如何让我的课程识别学生姓名？

1 个答案: