8.5 score.csv
    image.png

    1. 姓名,学号,C语言,Java,Python,VB,C++,总分
    2. 朱佳,0121701100511,75.2,93,66,85,88,407
    3. 李思,0121701100513,86,76,96,93,67,418
    4. 郑君,0121701100514, ,98,76, ,89,263
    5. 王雪,0121701100515,99,96,91,88,86,460
    6. 罗明,0121701100510,95,96,85,63,91,430
    1. 计算总分

    每次输入一个分数，重复10次，计算总分和平均分

    1. total = 0
    2. for i in range(10):
    3.     score = float(input())
    4.     total = total + score
    5. print(total)
    6. print(total / 10)
    1. 输入
    2. 89.5
    3. 56
    4. 25
    5. 89
    6. 78
    7. 100
    8. 65
    9. 88
    10. 36
    11. 99
    12. 输出
    13. 725.5
    14. 72.55

    在一行内输入用空格分隔的多个成绩，计算总分和平均分

    1. score = list(map(float, input().split(',')))
    2. # score = eval(input())  # 输入用逗号分隔的数值时可以用eval转为元组
    3. print(sum(score))
    4. print(sum(score) / len(score))
    1. 75.2,93,66,85,88
    2. 407.2
    3. 81.44

    2.字符串切片

    1. score = '朱佳,0121701100511,75.2,93,66,85,88,407'
    2. print(score[17:])               # 切片获得成绩部分数据'75.2,93,66,85,88,407'
    3. print(score[17:-4])               # 切片获得各门课程数据'75.2,93,66,85,88'
    4. print(sum(eval(score[17:-4])))  # eval将字符串转元组，sum()对元组求和，407.2

    3.字符串切分

    1. score = '朱佳,0121701100511,75.2,93,66,85,88,407'
    2. score_ls = score.split(',')
    3. print(score_ls)
    4. # ['朱佳', '0121701100511', '75.2', '93', '66', '85', '88', '407']
    5. print(score_ls[2:-1])  # ['75.2', '93', '66', '85', '88']
    6. print(sum(map(float,score_ls[2:-1])))  # 407.2
    7. print(sum(map(float,score_ls[2:-1]))/len(score_ls[2:-1]))  # 81.44
    1. 遍历文件8.5 score.csv
      1. 姓名,学号,C语言,Java,Python,VB,C++,总分
      2. 朱佳,0121701100511,75.2,93,66,85,88,407
      3. 李思,0121701100513,86,76,96,93,67,418
      4. 郑君,0121701100514, ,98,76, ,89,263
      5. 王雪,0121701100515,99,96,91,88,86,460
      6. 罗明,0121701100510,95,96,85,63,91,430
      1. # 读文件，逐行输出
      2. with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
      3.  for line in f:   # 遍历文件对象，依次获取文件的一行，字符串类型
      4.      print(line)  # 输出当前行，行末有换行符
      5.      # '姓名,学号,C语言,Java,Python,VB,C++,总分\n'
      ```python 姓名,学号,C语言,Java,Python,VB,C++,总分

    朱佳,0121701100511,75.2,93,66,85,88,407

    李思,0121701100513,86,76,96,93,67,418

    郑君,0121701100514, ,98,76, ,89,263

    王雪,0121701100515,99,96,91,88,86,460

    罗明,0121701100510,95,96,85,63,91,430

    1. ```python
    2. # 读文件，去掉行末换行符
    3. with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
    4.     for line in f:   # 遍历文件对象，依次获取文件的一行，字符串类型
    5.         print(line.strip())  # 输出当前行，行末有换行符
    6.         # '姓名,学号,C语言,Java,Python,VB,C++,总分\n'
    姓名,学号,C语言,Java,Python,VB,C++,总分
朱佳,0121701100511,75.2,93,66,85,88,407
李思,0121701100513,86,76,96,93,67,418
郑君,0121701100514, ,98,76, ,89,263
王雪,0121701100515,99,96,91,88,86,460
罗明,0121701100510,95,96,85,63,91,430

    # 读文件，每行输出为一个列表
with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
    for line in f:   # 遍历文件对象，依次获取文件的一行，字符串类型
        print(line.strip().split(','))  # 输出当前行，行末有换行符
        # ['姓名', '学号', 'C语言', 'Java', 'Python', 'VB', 'C++', '总分']

    ['姓名', '学号', 'C语言', 'Java', 'Python', 'VB', 'C++', '总分']
['朱佳', '0121701100511', '75.2', '93', '66', '85', '88', '407']
['李思', '0121701100513', '86', '76', '96', '93', '67', '418']
['郑君', '0121701100514', ' ', '98', '76', ' ', '89', '263']
['王雪', '0121701100515', '99', '96', '91', '88', '86', '460']
['罗明', '0121701100510', '95', '96', '85', '63', '91', '430']

    # 读文件，拼接为一个列表
with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
    score = []
    for line in f:   # 遍历文件对象，依次获取文件的一行，字符串类型
        score = score + line.strip().split(',')  # 输出当前行，行末有换行符
print(score)

    ['姓名', '学号', 'C语言', 'Java', 'Python', 'VB', 'C++', '总分', '朱佳', '0121701100511', '75.2', '93', '66', '85', '88', '407', '李思', '0121701100513', '86', '76', '96', '93', '67', '418', '郑君', '0121701100514', ' ', '98', '76', ' ', '89', '263', '王雪', '0121701100515', '99', '96', '91', '88', '86', '460', '罗明', '0121701100510', '95', '96', '85', '63', '91', '430']

    # 读文件，拼接为一个列表，用切片方法获取各列数据
with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
    score = []
    for line in f:   # 遍历文件对象，依次获取文件的一行，字符串类型
        score = score + line.strip().split(',')  # 输出当前行，行末有换行符
print(score[::8])   # ['姓名', '朱佳', '李思', '郑君', '王雪', '罗明']
print(score[4::8])  # ['Python', '66', '96', '76', '91', '85']
print(score[7::8])  # ['总分', '407', '418', '263', '460', '430']

    5.读文件转二维列表

    with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
    score = []
    for line in f:   # 遍历文件对象，依次获取文件的一行，字符串类型
        score.append(line.strip().split(','))  # 输出当前行，行末有换行符
print(score)

    # 用列表推导式实现
with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
    score = [line.strip().split(',') for line in f]
print(score)

    [['姓名', '学号', 'C语言', 'Java', 'Python', 'VB', 'C++', '总分'], 
 ['朱佳', '0121701100511', '75.2', '93', '66', '85', '88', '407'], 
 ['李思', '0121701100513', '86', '76', '96', '93', '67', '418'], 
 ['郑君', '0121701100514', ' ', '98', '76', ' ', '89', '263'], 
 ['王雪', '0121701100515', '99', '96', '91', '88', '86', '460'], 
 ['罗明', '0121701100510', '95', '96', '85', '63', '91', '430']]

    # 用推导式从二维列表中获取各列数据
with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
    score = [line.strip().split(',') for line in f]
print(score)
user = [x[0] for x in score]
print(user)  # ['姓名', '朱佳', '李思', '郑君', '王雪', '罗明']
python = [x[4] for x in score]
print(python)  # ['Python', '66', '96', '76', '91', '85']
total = [x[-1] for x in score]
print(total)   # ['总分', '407', '418', '263', '460', '430']

    6.读文件转字典

    score = []
with open('../data/csv/8.5 score.csv','r',encoding='utf-8') as f:
    title = f.readline().strip().split(',')
    for line in f:
        ls = line.strip().split(',')
        dic = dict(zip(title,ls))
        score.append(dic)
print(score)

    [
 {'姓名': '朱佳', '学号': '0121701100511', 'C语言': '75.2', 'Java': '93', 'Python': '66', 'VB': '85', 'C++': '88', '总分': '407'}, 
 {'姓名': '李思', '学号': '0121701100513', 'C语言': '86', 'Java': '76', 'Python': '96', 'VB': '93', 'C++': '67', '总分': '418'}, 
 {'姓名': '郑君', '学号': '0121701100514', 'C语言': ' ', 'Java': '98', 'Python': '76', 'VB': ' ', 'C++': '89', '总分': '263'}, 
 {'姓名': '王雪', '学号': '0121701100515', 'C语言': '99', 'Java': '96', 'Python': '91', 'VB': '88', 'C++': '86', '总分': '460'}, 
 {'姓名': '罗明', '学号': '0121701100510', 'C语言': '95', 'Java': '96', 'Python': '85', 'VB': '63', 'C++': '91', '总分': '430'}
 ]
    1. pandas读文件 ```python import pandas as pd

    score = pd.read_csv(‘../data/csv/8.5 score.csv’) print(score) # dataframe 格式

    ```python
   姓名            学号   C语言  Java  Python  VB  C++   总分
0  朱佳  121701100511  75.2    93      66  85   88  407
1  李思  121701100513    86    76      96  93   67  418
2  郑君  121701100514          98      76       89  263
3  王雪  121701100515    99    96      91  88   86  460
4  罗明  121701100510    95    96      85  63   91  430

    import pandas as pd

score = pd.read_csv('../data/csv/8.5 score.csv')

print(score.columns.tolist())  # 列表，['姓名', '学号', 'C语言', 'Java', 'Python', 'VB', 'C++', '总分']
print(score.values.tolist())   # 二维列表
score_ls = [score.columns.tolist()]+score.values.tolist()
print(score_ls)

    [['姓名', '学号', 'C语言', 'Java', 'Python', 'VB', 'C++', '总分'], 
 ['朱佳', 121701100511, '75.2', 93, 66, '85', 88, 407], 
 ['李思', 121701100513, '86', 76, 96, '93', 67, 418], 
 ['郑君', 121701100514, ' ', 98, 76, ' ', 89, 263], 
 ['王雪', 121701100515, '99', 96, 91, '88', 86, 460], 
 ['罗明', 121701100510, '95', 96, 85, '63', 91, 430]]