python - 让我的输出以某种方式显示时出现问题

Question

感谢您查看我的问题，并提前感谢您提供的任何帮助。我正在编写一个程序，它从 txt 文件中读取行，然后以某种方式打印输出。他们都在这里

这是我正在阅读的txt文件

JOE FRITZ           AMERICAN GOVERNMENT           B
JOE FRITZ           CALCULUS I                    A
JOE FRITZ           COMPUTER PROGRAMMING          B
JOE FRITZ           ENGLISH COMPOSITION           A
LANE SMITH          FUND. OF DATA PROCESSING      B
LANE SMITH          INTERMEDIATE SWIMMING         A
LANE SMITH          INTRO. TO BUSINESS            C
JOHN SPITZ          CHOIR                         C
JOHN SPITZ          COLLEGE STATISTICS            B
JOHN SPITZ          ENGLISH LITERATURE            D
JOHN SPITZ          INTRO. TO BUSINESS            B

我试图让我的输出看起来像这样:

                       GRADE REPORT

NAME                COURSE                            GRADE
-----------------------------------------------------------
JOE FRITZ           AMERICAN GOVERNMENT                 B
                    CALCULUS I                          A
                    COMPUTER PROGRAMMING                B
                    ENGLISH COMPOSITION                 A
                    Total courses taken = 4

LANE SMITH          FUND. OF DATA PROCESSING            B
                    INTERMEDIATE SWIMMING               A
                    INTRO. TO BUSINESS                  C
                    Total courses taken = 3

JOHN SPITZ          CHOIR                               C
                    COLLEGE STATISTICS                  B
                    ENGLISH LITERATURE                  D
                    INTRO. TO BUSINESS                  B
                    Total courses taken = 4

Total courses taken by all students = 11

Run complete.  Press the Enter key to exit.

编辑

感谢您的帮助，我完成了这个程序。

我知道这可能很难看，但我很高兴 ATM 的输出正确。

这是将显示正确输出的源代码:

#-----------------------------------------------------------------------
# VARIABLE DEFINITIONS

name = ""
previousName = ""
course = ""
grade = ""
grandTotal = 0
courseCount = 0
eof = False

#-----------------------------------------------------------------------
# CONSTANT DEFINITIONS

#-----------------------------------------------------------------------
# FUNCTION DEFINITIONS

def startUp():
    global gradeFile, grandTotal,courseCount, previousName, name
    grandTotal = 0
    courseCount = 0
    gradeFile = open("grades.txt","r")
    print
    print ("grade report\n").center(60).upper()
    print "name".upper(),"course".rjust(21).upper(),"grade".rjust(33).upper()
    print "-" * 60
    readRecord()


def readRecord():
    global name, course, grade, eof, courseCount

    studentRecord = gradeFile.readline()
    if studentRecord == "":
        eof = True
    else:
        name = studentRecord[0:20]
        course = studentRecord[20:50]
        grade = studentRecord[50:51]
        eof = False

def processRecords():
    global courseCount, previousName, name, grandTotal
    while not eof:
        if name != previousName:
            if name == "JOE FRITZ           ":
                courseCount = 0
                print name + course + "       " + grade
                previousName = name
                courseCount += 1
            else:
                print "\t\t    Total courses taken =",courseCount 
                print
                courseCount = 0
                print name + course + "       " + grade
                previousName = name
                courseCount += 1
        else:
            print (" " * 20) + course + "       " + grade
            courseCount += 1
        grandTotal +=1
        readRecord()
    print "\t\t    Total courses taken =",courseCount


def closeUp():
    gradeFile.close()
    print "\nTotal courses taken by all students =",grandTotal

#-----------------------------------------------------------------------
# PROGRAM'S MAIN LOGIC

startUp()
processRecords()
closeUp()

raw_input("\nRun complete. Press the Enter key to exit.")

感谢大家的帮助。我真的很感激。抱歉，如果我在此过程中让任何人感到沮丧。祝你有个好的一天。和平

Answer 1

我只是弄清楚函数 readRecord() 中代码中的一个错误，您只是在读取文件的第一行；您应该遍历所有行或使 readRecord() 成为生成器。

  def readRecord():
     global name, course, grade, eof

     studentRecord = gradeFile.readline()  # <----- HERE

     if studentRecord == "":
        eof = True
     else:
        name = studentRecord[0:20]
        course = studentRecord[20:50]
        grade = studentRecord[50:51]
        eof = False

但尽管如此，说实话，我不太喜欢你的代码，如果我是你，我会这样做:

1) 以任何方式从文件中获取数据 (csv, regex ...) ;我想我们已经在 here 中找到了答案

2) 将数据放入字典或其他任何东西中(这样您就可以随心所欲地操作它们)。

3) 使用itertools.groupby()按学生分组并计算您想要的总和。

4) 使用字符串 Template() ，因为格式可能会改变，并且不要像您那样对输出格式进行硬编码。

并且请在编写完成后逐一测试您的功能，因为如果您不这样做，将很难找出代码的哪一部分不工作。

编辑:

而且我不会问你为什么要这样做，因为如果你想再次将它们放入文件中，如果你想再次检索它们，你将遇到与以前相同的问题，如果你的目标只是做出漂亮的输出我会问你值得吗？

最后一个建议使用众所周知的格式，如 csv、xml ...

祝你好运:)