陷入困境,你可以帮忙吗?

ele*_*357 0 python variable-assignment

我目前正在编写一个从txt文件中读取记录的程序,并在屏幕上打印数据:

                       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.
Run Code Online (Sandbox Code Playgroud)

这是它从中读取的文本文件:

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
Run Code Online (Sandbox Code Playgroud)

这是我的代码:

# VARIABLE DEFINITIONS

name = ""
course = ""
grade = ""
recordCount = 0
eof = False
gradeFile = ""

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

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

def startUp():
    global gradeFile
    gradeFile = open("grades.txt","r")
    print ("grade report\n").center(60).upper()
    print "name".upper(),"course".rjust(22).upper(),"grade".rjust(32).upper()
    print "-" * 60
    readRecord()

def readRecord():
    global name, course, grade

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

def processRecords():
    numOfRecs = 0
    while not eof:
        numOfRecs += 1
        printLine()
        readRecord()
    return numOfRecs

def printLine():
    print name, course.rjust(3), grade.rjust(3)

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

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

startUp()
recordCount = processRecords()
closeUp()

raw_input("\nRun complete. Press the Enter key to exit.")
Run Code Online (Sandbox Code Playgroud)

结果只是打印txt文件的最后一行并陷入循环.任何帮助将不胜感激.感谢您的时间.

Sri*_*aju 5

为什么不在一个功能中完成所有操作 -

def processRecords():
    print ("grade report\n").center(60).upper()
    print "name".upper(),"course".rjust(22).upper(),"grade".rjust(32).upper()
    print "-" * 60

    rec_count = 0
    for line in open("grades.txt","r"):
        name   = line[0:20]
        course = line[20:50]
        grade  = line[50:51]
        print name, course.rjust(3), grade.rjust(3)
        rec_count += 1
    return rec_count
Run Code Online (Sandbox Code Playgroud)

所有这些功能都在这一个功能中压缩.你似乎编程很像C代码.这是Python!

globals除非必须,否则尽量避免使用.只是我遵循的原则.显然在这种情况下你不需要.

  • 如果你的教练宁愿在一个简单的函数上使用全局变量,那么我会质疑他作为教练的优点.考虑将参数传递给函数,而不是全局变量. (2认同)