Question

在下面的代码中，我遇到了两件事。对于一个第40行（examPoints）和47（hwkPoints）函数中的数学运算正在第94行的列表中传递一系列值。它应该取得分数并将它们相加但由于某种原因它不是通过每个范围添加最后一个数字。

例如：对于myValues [11:13]，它传递了数字75,95和97，但它只添加前2而不是最后。

我的代码在这里：

from time import asctime
from time import localtime

def findGrade(myGrade): #argument number in range of 1 - 100 or float myNum?
    if myGrade >= 90:
        letterGrade = "A"
    if myGrade >= 80:
        letterGrade = "B"
    if myGrade >= 70:
        letterGrade = "C"
    if myGrade >= 60:
        letterGrade = "D"
    if myGrade < 60:
        letterGrade = "F"
    return letterGrade

def calculatePointsEarned(hwkGrades, examGrades):
    hwkTotal = float(hwkPoints(hwkGrades))
    #print hwkTotal
    examTotal = float(examPoints(examGrades))
    #print examTotal
    myAverage = (hwkTotal + examTotal) / possiblePoints
    myAverage = myAverage * 100.0
    #myAverage = int(myAverage)
    return myAverage

def totalPoints(hwkGrades, examGrades):
    hwkTotal = int(hwkPoints(hwkGrades))
    examTotal = int(examPoints(examGrades))
    allPoints = str((hwkTotal + examTotal))
    return allPoints


#Create newtimeline using day of week, space, month, space, day, space, year, space time from asctime function
def timeMessage():
    localtime()
    newTimeline = asctime()
    return newTimeline

def examPoints(examValues):
    myGrades = 0
    for grade in examValues:
        myGrades = int(grade) + myGrades
    #print str(myGrades) + " exam\n" 
    return myGrades

def hwkPoints(hwkValues):
    myGrades = 0
    for grade in hwkValues:
        myGrades = int(grade) + myGrades
    #print str(myGrades) + " hwk" 
    return myGrades

def requestMessage (myValues, myTime):
    nameLine = myValues[1] + ", " + myValues[2] + "\t" + myValues[0] + "\t" + myValues[3]
    examScore = "Exam " + "- " + myValues[11] + ", " + myValues[12] + ", " + myValues[13]
    hwkScore = "Homework " + "- " + myValues[4] + ", " + myValues[5] + ", " + myValues[6] + ", " + myValues[7] + ", " + myValues[8]  + ", " + myValues[9] + ", " + myValues[10]
    pointsEarned = "Total points earned " + "- " + totalPoints(myValues[4:10], myValues[11:13])
    myGrade = "Grade:  " + str(theAverage) + " that is a " + findGrade(theAverage)
    message = nameLine + "\n" + examScore + "\n" + hwkScore + "\n" + pointsEarned + "\n" + myGrade + "\n" + myTime
    return message

def fileOutput(studentID, lastName, firstName, dateTime):
    myLine = studentID + " " + lastName + ", " + firstName + " " + dateTime + "\n"
    return myLine


#Create input stream from grades.dat and assign to infile
inFile = open('grades.dat', "r")

#Create output stream to results.dat and assign to outfile
outFile = open('results.dat', 'w+')

myTime = timeMessage()
theAverage = 0
theLettergrade = ""
theMessage = ""
possiblePoints = 550
theRequest = ""

studentID = raw_input("Please input student ID: ")
myLine = "notemptystring"

while myLine != "": #may be wrong Is myline not equal to the empty string?
    myLine = inFile.readline() #may be wrong Read line from infile and assign to myline
    myLine = myLine.strip('\r\n')

    myValues = myLine.split(",") #Separate values in myline and assign to myvalues

    if studentID == myValues[0]:
        #print myValues

        #Call calculatePointsEarned function with a list of homework values and a list of exam values and assign to theaverage
        theAverage = calculatePointsEarned(myValues[4:10], myValues[11:13])
        #print theAverage

        theLettergrade = findGrade(theAverage) #Call findGrade function with theaverage and assign to thelettergrade)
        #print theLettergrade

        #Call fileOutput function with studentid, lastname, firstname, and datetime to get message for writing to output file, and assign to therequest
        theRequest = fileOutput(myValues[0], myValues[1], myValues[2], timeMessage())
        #print theRequest

        theMessage = requestMessage(myValues, timeMessage()) #Call requestMessage with myline and mytime for message to display, and assign to themessage

        #Write theRequest to outfile
        outFile.write(theRequest)

        print theMessage

    else: #is studentid not equal to first element in myValues
        "Do Nothing"


#close infile and outfile
inFile.close()
outFile.close()

编辑：很抱歉，我在找到正确的代码时遇到了问题。

Answer 1

对于myValues [11:13]它正在传递数字75,95和97，但它只添加前2而不是最后

myValues[11:13]选择两个元素，而不是三个元素。结束指数（13）不包括在范围内。

阅读Explain Python's slice notation

Python从未正确添加的列表中传递值

1 个答案: