Python uses classes to implement a simple student grade management system

Document 对象参考手册Python3 Examples

We will use Python classes to implement a simple student grade management system. This system will allow us to add students, record their grades, and calculate each student's average grade.

Example

class Student:
    def __init__(self, name):
        self.name = name
        self.grades = []

    def add_grade(self, grade):
        self.grades.append(grade)

    def average_grade(self):
        return sum(self.grades) / len(self.grades) if self.grades else 0

class GradeManager:
    def __init__(self):
        self.students = []

    def add_student(self, name):
        self.students.append(Student(name))

    def get_student(self, name):
        for student in self.students:
            if student.name == name:
                return student
        return None

    def add_grade_to_student(self, name, grade):
        student = self.get_student(name)
        if student:
            student.add_grade(grade)
        else:
            print(f"Student {name} not found.")

    def show_average_grades(self):
        for student in self.students:
            print(f"{student.name}'s average grade is {student.average_grade():.2f}")

# Example usage
manager = GradeManager()
manager.add_student("Alice")
manager.add_student("Bob")

manager.add_grade_to_student("Alice", 90)
manager.add_grade_to_student("Alice", 85)
manager.add_grade_to_student("Bob", 78)
manager.add_grade_to_student("Bob", 82)

manager.show_average_grades()

Code analysis:

  1. StudentClass: represents a student, containing the student's name and grade list.add_gradeMethod used to add grades,average_gradeMethod used to calculate the average grade.
  2. GradeManagerClass: manages all students.add_studentMethod used to add a student,get_studentMethod used to find a student by name,add_grade_to_studentMethod used to add a grade for a specified student,show_average_gradesMethod used to display the average grade of all students.
  3. Example usage section: created aGradeManagerinstance, added two students, added grades for each student, and finally displayed each student's average grade.

Output result:

Alice's average grade is 87.50
Bob's average grade is 80.00

Document 对象参考手册Python3 Examples

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