Question

def calculateGrades():
  file = open(pickAFile(), "rt")
  highestGrade(file)
  lowestGrade(file)

def highestGrade (file): 
  lines= file.readlines()
  file.close   
  len_lines_file = len(lines) 
  lines = lines[1:len_lines_file]

  highest_Grade = 0.0 
  parts = lines[0].split(",")
  highest_Grade = int(parts[2]) 
  for line in lines:
    parts = line.split(",")
    if int(parts[2]) > highest_Grade:
      highest_Grade = int(parts[2])
def lowestGrade(file):
  open(file(, "rt")
  lines= file.readlines()
  file.close()
  len_lines_file = len(lines) 
  lines = lines[1:len_lines_file]

  lowest_Grade = 0.0
  parts = lines[0].split(",")
  lowest_Grade = int(parts[2]) 
  for line in lines:
    parts = line.split(",")
    if int(parts[2]) < lowest_Grade:
      lowest_Grade = int(parts[2])
  print lowest_Grade
calculateGrade()

calculateGrade（）是我教授所说的“霸主”功能。我试图在LowestGrade和highestGrade函数中运行主函数中提取的文件，但它一直给我O / I错误，我不知道该怎么做。

Answer 1

当您在运行lowestGrade()后尝试立即运行highestGrade()时，似乎会出现错误。发生这种情况是因为您已在highestGrade()中关闭了该文件，但未在lowestGrade()中正确打开该文件：lowestGrade()定义中的第一行应为file = open(pickAFile(), "rt")。

通常，最好使用with块打开文件，例如：

with open(pickAFile(), "rt") as file:
    lines= file.readlines()
### file.close() is automatically called by Python at the end of the with block

所以一个选项是从highestGrade和lowestGrade函数中删除打开/关闭行，并在外面执行，比如说

def calculateGrades():
  with open(pickAFile(), "rt") as file:
    highestGrade(file)
    lowestGrade(file)

但是，您可能需要考虑使用parts作为lowestGrade和highestGrade的参数，并在函数外计算它：

def calculateGrades():
  with open(pickAFile(), "rt") as file:
    lines= file.readlines()
  len_lines_file = len(lines) 
  lines = lines[1:len_lines_file]
  parts = lines[0].split(",")
  highestGrade(parts)
  lowestGrade(parts)

并根据需要截断highestGrade和lowestGrade中的代码。

JES：关闭文件错误的I / O操作

1 个答案: