Question

所以这让我发疯了。我需要一个包含（所有在一行）的文本文件

mmfff m fm fmm FFF mmmmmm mfmfmf mmmfff MM fmmmf

并在程序中操作它。它需要打开并读取文件，编辑空格，并将所有字母更改为大写字母。然后它需要打印编辑过的文件，计算m和f并将它们输出为整体的百分比。

# A program to determine male to female ratio

import math

main = raw_input("Enter the name of your file: ")

inputFile = open(main, 'r+')

gender =(inputFile.read().replace(" ", "").replace("f", "F").replace("m", "M"))

inputFile.close()

inputFile= open(main, 'r+')

inputFile.write(gender)

inputFile.close()

print gender

fletter = 0

mletter = 0

mletter = gender.count('M')

fletter = gender.count('F')

mletter =((mletter*100)/39)*1.0

fletter =((fletter*100)/39)*1.0

print "There are", mletter, " males and", fletter, " females."

我尝试了很多方法，现在我甚至都记不起来了！我的问题是它没有正确编辑txt文件，我在字符串的末尾有多余的字母。并且它最终拒绝围绕我的数学运算，所以当它应该是59时我最终会得到58和41.而且我确实尝试了圆函数，没有帮助。

Answer 1

我在下面的代码中做了一些改进。内联注释解释了每个部分的作用以及它对您的初始尝试所做的改进。

main = raw_input("Enter the name of your file: ")

# make this a function since we use the equation more than once
def get_percent(part, whole):
    return 100 * float(part)/float(whole)

# make sure we handle the file not existing
try:
    with open(main, 'r+') as fd:
        # replace
        newstr = fd.read().replace(' ', '').upper()
        # after reading the file the file pointer will be at the end, we need to seek
        # back to the start of the file
        fd.seek(0)
        # remove the existing file contents
        fd.truncate()
        fd.write(newstr)
except IOError:
    # provide a friendly error and exit instead of a stacktrace
    raise SystemExit("Failed to open file %s" % main)


mletter = newstr.count('M')
fletter = newstr.count('F')
total = len(newstr)

# Using string formatting is often easier to read than string concatentation
print "There are %s%% males and %s%% females" %(
                                                get_percent(mletter, total),
                                                get_percent(fletter, total)
                                               )

Python：在文本文件中编辑字符串时遇到问题

1 个答案: