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，从txt文件中读取行，然后以某种方式打印输出。在这里他们都是
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.
修改
感谢您的帮助，我完成了这个计划。
我知道这可能很难看，但ATM我很高兴能让输出正确。
以下是显示正确输出的来源：
#-----------------------------------------------------------------------
# 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。对不起，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
答案 0 :(得分：3)
我只是在函数readRecord（）中找出代码中的一个错误，你只是在阅读文件的第一行;你应该遍历所有行或使readRecord（）成为一个生成器。
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
但是尽管如此，为了真诚，我不喜欢你的代码，如果我是你，我会做的就是：
1）以任何方式从文件中获取数据（csv，regex ...）;我想我们已经在here
中得到了答案2）将数据放入字典或其他内容（这样你就可以操纵它们了。）
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，并且不像你那样硬编码输出格式。
并且请在写入之后逐个测试您的功能，因为如果不这样做，将很难弄清楚代码的哪个部分不起作用。
修改
我不会问你为什么要这样做，因为如果你想再把它们放在一个文件中，你会遇到和以前一样的问题，如果你想再次检索它们，如果你的目标只是为了做一个漂亮的输出我会问你是否值得？
最后一个建议使用熟知的格式，如csv，xml ......
祝你好运:)。
答案 1 :(得分：0)
这可能不是您的愚蠢教练希望您这样做的20世纪60年代COBOLlocks方式，但一般的想法是：
（1）itertools.groupby可以为您节省所有先前/当前检测名称更改的malarky
（2）你应该预先将你的数据记录提取成合理的格式 - 剥离尾随空格（总是一个好主意）摆脱不属于数据的杂散换行
（3）像你一样使用的全局变量是完全的痘（用任何语言）。
import itertools
guff = """\
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
"""
data_source = guff.splitlines(True) # simulate file
columns = (slice(0, 20), slice(20, 50), slice(50, 51))
def data_reader(raw_record_iterator):
for line in raw_record_iterator:
yield [line[sl].rstrip() for sl in columns]
def process_file():
# f = open('my_file.text', 'r')
# or use a 'with' statement
# data_source = f
for key, grouper in itertools.groupby(
data_reader(data_source), lambda element: element[0]):
print "=== start student %s ===" % key
for cooked_record in grouper:
print cooked_record
print "=== end student %s ===" % key
print "=== Grand totals here ==="
# f.close()
if __name__ == "__main__":
process_file()
实际输出：
=== start student JOE FRITZ ===
['JOE FRITZ', 'AMERICAN GOVERNMENT', 'B']
['JOE FRITZ', 'CALCULUS I', 'A']
['JOE FRITZ', 'COMPUTER PROGRAMMING', 'B']
['JOE FRITZ', 'ENGLISH COMPOSITION', 'A']
=== end student JOE FRITZ ===
=== start student LANE SMITH ===
['LANE SMITH', 'FUND. OF DATA PROCESSING', 'B']
['LANE SMITH', 'INTERMEDIATE SWIMMING', 'A']
['LANE SMITH', 'INTRO. TO BUSINESS', 'C']
=== end student LANE SMITH ===
=== start student JOHN SPITZ ===
['JOHN SPITZ', 'CHOIR', 'C']
['JOHN SPITZ', 'COLLEGE STATISTICS', 'B']
['JOHN SPITZ', 'ENGLISH LITERATURE', 'D']
['JOHN SPITZ', 'INTRO. TO BUSINESS', 'B']
=== end student JOHN SPITZ ===
=== Grand totals here ===