如何处理Python代码中的特殊情况？

Question

我有以下Python作业：

文件如下所示：

我被要求在计算中处理一些特殊情况。例如，当我有25/0这样的值时，它就会变成一个错误。我怎么能做到呢？在

这是我当前的代码：

import os.path
fLocation="//Users//Ivan//Desktop//"
print("Assumed file location is at: ", fLocation)
fName = input("\nPlease enter a file name with its extension (ex. XXX.txt): ")

fin = open(fLocation + fName, 'r')

fLinesList=fin.readlines()

fin.close()
print('*' * 50, "\nData items have been read from file:\n\t"
                         + fLocation + fName + '\n')

print('-' * 30, "\nThe list of the lines in the file:\n", fLinesList)

print("\nThere are", len(fLinesList), "lines\n")

          # Print file content line by line
print('\n' + '-' * 30 + '\nFile "' + fName + '" contains:\n')
print(fLinesList[0].strip())
print(fLinesList[1].strip())
print(fLinesList[2].strip())
print(fLinesList[3].strip())
print(fLinesList[4].strip())
print(fLinesList[5].strip())

wordsInLine4 = fLinesList[4].split()
print('-' * 30, "\nwords in line4  =", wordsInLine4)
QualityPointsprevious=float(wordsInLine4[6])
HoursAttemptedprevious=float(wordsInLine4[2])
GPAprevious=format(QualityPointsprevious/HoursAttemptedprevious,'.2f')

wordsInLine5 = fLinesList[5].split()
print('-' * 30, "\nwords in line5  =", wordsInLine5)

QualityPointsnow=float(wordsInLine5[6])
HoursAttemptednow=int(wordsInLine5[2])
GPAnow=format(QualityPointsnow/HoursAttemptednow,'.2f')
if (OverallHoursAttempted==0,OverallQualityPoints!=0):
    OverallGPA==-1
else:
    if (OverallHoursAttempted==0,OverallQualityPoints==0):
        OverallGPA==0
    else:
        if (GPAprevious==-1):
            OverallGPA==-1
OverallQualityPoints=QualityPointsprevious+QualityPointsnow
OverallHoursAttempted=HoursAttemptedprevious+HoursAttemptednow
OverallGPA=format(OverallQualityPoints/OverallHoursAttempted,'.2f')
QualityPointsprevious=str(QualityPointsprevious)
HoursAttemptedprevious=str(HoursAttemptedprevious)
QualityPointsnow=str(QualityPointsnow)
HoursAttemptednow=str(HoursAttemptednow)



save_path='C:\\TEMP\\'

text1=fLinesList[0]
text2=fLinesList[1]
text3=fLinesList[2]
text4=fLinesList[3]

text5=fLinesList[4]
text51=fLinesList[5]
text6="\n---------------------------"
text7="\nPrevious GPA:\t"+GPAprevious
text8="\nCurrent GPA:\t"+GPAnow
text9="\nOverall GPA:\t"+OverallGPA

text1=str(text1)
text2=str(text2)
text3=str(text3)
text4=str(text4)
text5=str(text5)
text51=str(text51)
text6=str(text6)
text7=str(text7)
text8=str(text8)
text9=str(text9)

wordsInLine0 = fLinesList[0].split()
print('-' * 30, "\nwords in line0  =", wordsInLine0)

lnameofstudent=wordsInLine0[2]
fnameofstudent=wordsInLine0[1]

lnameofstudent=str(wordsInLine0[2])
fnameofstudent=str(wordsInLine0[1])

name=fnameofstudent+" "+lnameofstudent

saveFile=open("C://TEMP//"+name+".txt","w")

saveFile.write(text1)
saveFile.write(text2)
saveFile.write(text3)
saveFile.write(text4)
saveFile.write(text5)
saveFile.write(text51)
saveFile.write(text6)
saveFile.write(text7)
saveFile.write(text8)
saveFile.write(text9)
saveFile.close()

Answer 1

我没有读你的代码，因为它太长了，我被你想要的东西弄糊涂了，因为它是非描述性的（无意冒犯）。但你会问“我该如何破例？”您可以使用Exception作为超类（这是正确的术语吗？）。下面是一个例子：

class MyError(Exception): #exception names usually end with 'Error'
    pass

这应该是开始创建自定义异常的方法，您可以稍后了解更多。希望这有点帮助。在

编辑： 记住不要创建任何具有类似内置异常的自定义异常，例如ZeroDivisionError。在