Python - Edited

import pandas as pd
import matplotlib.pyplot as plt

def menu():
    print('+--------- MENU ---------+')
    print('| 1. Import excel file   |')
    print('| 2. Print all data      |')
    print('| 3. Calculation         |')
    print('| 4. Stats               |')
    print('| 5. Update data         |')
    print('| 6. Export excel file   |')
    print('| 7. Print menu          |')
    print('| 8. Exit                |')
    print('+------------------------+')


def import_file():
    while True:
        try:
            global data
            file_path = input('Enter path: ')
            # print in row
            pd.set_option('expand_frame_repr', False)
            data = pd.read_excel(file_path)
            pd.options.display.max_rows = 100
            pd.options.display.max_columns = 20
            print('Success\n')
            break
        except IOError:
           print ("Error: can\'t find file or read data")

def print_data():
    print('\n', data.to_string(index=False), '\n')


def calculation(score):
    data['Quiz'] = round((data['Quiz 1'] + data['Quiz 2'] + data['Quiz 3']) / 3 + data['Bonus'] - data['Minus'], 1)
    data['GPA'] = round(score[0] * data['Quiz'] + score[1] * data['Midterm'] + score[2] * data['Final'], 1)
    i = 0
    for x in data['GPA']:
        if x >= 90:
            data.loc[i, 'Rank'] = 'A+'
        elif x >= 80:
            data.loc[i, 'Rank'] = 'A'
        elif x >= 70:
            data.loc[i, 'Rank'] = 'B+'
        elif x >= 60:
            data.loc[i, 'Rank'] = 'B'
        elif x >= 50:
            data.loc[i, 'Rank'] = 'C+'
        else:
            data.loc[i, 'Rank'] = 'F'

        if x >= 50:
            data.loc[i, 'Status'] = 'Pass'
        else:
            data.loc[i, 'Status'] = 'Fail'
        i += 1
    print('Success\n')


def stats():
    mean = round(data['GPA'].mean(), 1)
    print('\n* Mean GPA =', mean)

    std = round(data['GPA'].std(), 1)
    print('* Stdev GPA =', std)

    min_index = data['GPA'].idxmin()
    print('* Min GPA:\n', data.loc[[min_index]].to_string(index=False))

    max_index = data['GPA'].idxmax()
    print('* Max GPA:\n', data.loc[[max_index]].to_string(index=False))

    c_pass = len(data[data['Status'] == 'Pass'])
    print('* Num pass =', c_pass)

    c_fail = len(data[data['Status'] == 'Fail'])
    print('* Num fail =', c_fail, '\n')

    # Bar Chart
    # Data
    r = [0, 2, 4, 6, 8, 10]

    c_quiz1_50 = len(data[data['Quiz 1'] < 50])
    c_quiz2_50 = len(data[data['Quiz 2'] < 50])
    c_quiz3_50 = len(data[data['Quiz 3'] < 50])
    c_quiz_50 = len(data[data['Quiz'] < 50])
    c_mid_50 = len(data[data['Midterm'] < 50])
    c_final_50 = len(data[data['Final'] < 50])

    c_quiz1_50_80 = len(data[data['Quiz 1'] < 80]) - c_quiz1_50
    c_quiz2_50_80 = len(data[data['Quiz 2'] < 80]) - c_quiz2_50
    c_quiz3_50_80 = len(data[data['Quiz 3'] < 80]) - c_quiz3_50
    c_quiz_50_80 = len(data[data['Quiz'] < 80]) - c_quiz_50
    c_mid_50_80 = len(data[data['Midterm'] < 80]) - c_mid_50
    c_final_50_80 = len(data[data['Final'] < 80]) - c_final_50

    c_quiz1_80 = len(data[data['Quiz 1'] >= 80])
    c_quiz2_80 = len(data[data['Quiz 2'] >= 80])
    c_quiz3_80 = len(data[data['Quiz 3'] >= 80])
    c_quiz_80 = len(data[data['Quiz'] >= 80])
    c_mid_80 = len(data[data['Midterm'] >= 80])
    c_final_80 = len(data[data['Final'] >= 80])

    raw_data = {'greenBars': [c_quiz1_50, c_quiz2_50, c_quiz3_50, c_quiz_50, c_mid_50, c_final_50],
                'orangeBars': [c_quiz1_50_80, c_quiz2_50_80, c_quiz3_50_80, c_quiz_50_80, c_mid_50_80, c_final_50_80],
                'blueBars': [c_quiz1_80, c_quiz2_80, c_quiz3_80, c_quiz_80, c_mid_80, c_final_80]}
    df = pd.DataFrame(raw_data)

    # From raw value to percentage
    totals = [i + j + k for i, j, k in zip(df['greenBars'], df['orangeBars'], df['blueBars'])]
    greenBars = [i / j * 100 for i, j in zip(df['greenBars'], totals)]
    orangeBars = [i / j * 100 for i, j in zip(df['orangeBars'], totals)]
    blueBars = [i / j * 100 for i, j in zip(df['blueBars'], totals)]

    # plot
    barWidth = 0.85
    names = ('Quiz 1', 'Quiz 2', 'Quiz 3', 'Quiz', 'Midterm', 'Final')
    # Create green Bars
    p1 = plt.bar(r, greenBars, color='#b5ffb9', edgecolor='white', width=barWidth)
    # Create orange Bars
    p2 = plt.bar(r, orangeBars, bottom=greenBars, color='#f9bc86', edgecolor='white', width=barWidth)
    # Create blue Bars
    p3 = plt.bar(r, blueBars, bottom=[i + j for i, j in zip(greenBars, orangeBars)], color='#a3acff', edgecolor='white',
                 width=barWidth)

    # Custom x axis
    plt.xticks(r, names)
    plt.xlabel("Scores")
    plt.legend((p1[0], p2[0], p3[0]), ('score < 50', '50 <= score < 80 ', 'score >= 80'))

    # Box Plot
    plt.subplots(figsize=(5, 5), dpi=88)
    plt.title('Box Plot')
    plt.ylabel('GPA')
    plt.boxplot(data['GPA'])

    # Pie Chart
    labels = ['F', 'C+', 'B', 'B+', 'A', 'A+']
    values = [len(data[data['Rank'] == 'F']), len(data[data['Rank'] == 'C+']), len(data[data['Rank'] == 'B']),
              len(data[data['Rank'] == 'B+']), len(data[data['Rank'] == 'A']), len(data[data['Rank'] == 'A+'])]
    fig1, ax1 = plt.subplots(figsize=(5, 5), dpi=88)
    plt.title('Pie Chart')
    ax1.pie(values, labels=labels, autopct='%1.1f%%', startangle=90)
    plt.legend(labels=labels)

    plt.show()


def bar_label(ps):
    for p in ps:
        plt.text(p.get_x() + p.get_width() / 2., p.get_y() + p.get_height() / 2.,
                 '%.1f' % p.get_height() + '%', ha='center', va='center')


def update_data():
    global score
    while True:
        print()
        # Choose student
        while True:
            i = eval(input('Input No.: '))
            if i > len(data):
                print('No. out of range.')
            else:
                print('\n', data.loc[[i - 1]].to_string(index=False))
                break

        # Check whether that is the needed student
        re_print = 0
        while True:
            y = input('Do you want to continue to change the data of this student? (Y/N): ')
            if y != 'Y'and y != 'N':
                print('Wrong input.')
            elif y == 'Y':
                list_col = ['Quiz 1', 'Quiz 2', 'Quiz 3', 'Bonus', 'Minus']
                while True:
                    col_name = input('Input Col name: ')
                    if col_name in list_col:
                        break
                    else:
                        print('The change can only be made for Quiz 1, Quiz 2, Quiz 3, Bonus, Minus.')

                while True:
                    new_value = eval(input('Input new value: '))
                    if new_value < 0 or new_value > 100:
                        print("Wrong input.")
                    else:
                        break

                data.loc[i - 1, col_name] = new_value
                re_print = 1
                if len(score) == 3:
                    calculation(score)
            else:
                if re_print == 1:
                    print('\n', data.loc[[i - 1]].to_string(index=False))
                break

        # Continue to chang data
        while True:
            k = input('Do you want to change anything else? (Y/N): ')
            if k != 'Y' and k != 'N':
                print('Wrong input.')
            else:
                break
        if k == 'N':
            print()
            break


def export_file():
    while True:
        try:
            file_path = input('Enter export path: ')
            data.to_excel(file_path, index=False)
            print('Success\n')
            break
        except ValueError:
            print("Error: invalid input.")


data = ''
menu()
print("Inport excel file")
import_file()
score = ''
while True:
    try:
        n = eval(input('Input a number: '))
        if n == 1:
            import_file()
        elif n == 2:
            print_data()
        elif n == 3:
            while True:
                try:
                    score = [float(x) for x in input('Input % [Quiz, Midterm, Final]: ').split(',')]
                    if score[0] + score[1] + score[2] != 1:
                        print("Wrong input.")
                    else:
                        calculation(score)
                        print_data()
                        break
                except ValueError:
                    print("Error: invalid input.")
                except IndexError:
                    print("Error: invalid input.")

        elif n == 4:
            if len(score) != 3:
                print("Calculation must be done before Stats.")
            else:
                stats()
        elif n == 5:
            update_data()
        elif n == 6:
            export_file()
        elif n == 7:
            menu()
        elif n == 8:
            exit()
        else:
            print('Please enter a number between 1 and 8!')
    except NameError:
       print ("Error: invalid input.")
    except SyntaxError:
       print ("Error: invalid input.")