如何使用命令行 sys.argv Python3

问题描述

我想使用 sys.argv[] 从命令行获取 5 个数字的列表到函数 (def calc_avg)，以便对它们求平均值。但我不断得到 - TypeError: int() argument must be a string,a bytes-like object or a number,not 'list'。

import sys


def calc_avg(grades):
    average = sum(grades) / len(grades)
    return average


def get_letter(averaged_grades):
    if averaged_grades >= 90:
        return "A"
    elif averaged_grades >= 80:
        return "B"
    elif averaged_grades >= 70:
        return "C"
    elif averaged_grades >= 60:
        return "D"
    elif averaged_grades < 59:
        return "F"


def print_results(average,letter_grade):
    print(f"Average: {average}")
    print(f"Letter grade: {letter_grade}")


try:
    number_lst = int(sys.argv[1:])


except ValueError:
    print("Error,all grades must be numeric.")

calculated_average = calc_avg(number_lst)
letter_grade = get_letter(calculated_average)
print_results(calculated_average,letter_grade)

解决方法

您无法将 list 转换为 int，您必须构建一个新列表，将您的参数一一转换：

number_lst = [int(i) for i in sys.argv[1:]]