我發現文件末尾是空的，python

Question

請您需要您的幫助，我想將compy中的某些特定行從compy複製到另外兩個文件。 變量n和p是全局的。 這裏是我的代碼：

def files(): 
    i = 1 
    X = 1 
    f90 = open('C:\Users\Homura\Desktop\python\data90.txt' , 'w') 
    f10 = open('C:\Users\Homura\Desktop\python\data10.txt' , 'w') 
    f = open('C:\Users\Homura\Desktop\python\TData.txt' , 'r') 
    while True: 
     line = f.readline() 
     if line.startswith('0'): 
      while i <= n: # taking 90% of negative tweets and writing them in f90 
       f90.write(line) 
       i += 1 
      while i != n: #putting the rest of the negative tweets (10%) in the f10 file 
       f10.write(line) 
       i += 1 
     elif line.startswith('1'): 
      while (x <= p): # taking 90% of positive tweets and writing them in f90 
       f90.write(line) 
       x += 1 
      while (x != p): #putting the rest of the positive tweets (10%) in the f10 file 
       f10.write(line) 
       x += 1     

    f.close() 
    f10.close() 
    f90.close() 
    return f10 , f90 

Answer 1

首先，一個小的觀察，你有一個大寫X和小寫x - 他們應該是一樣的嗎？

X = 1 
#... 
x += 1 

接下來，線條不會以您認爲自己開始的字符開頭。 考慮添加一個else，以便在開始時既不輸入0也不輸出1。

最後，既然你說while True不清楚如何while循環終止，所以也許它不會和文件永遠不會關閉。嘗試只是在做對文件中的行...（見例如here）

試試這個：

for line in f: 
     if line.startswith('0'): 
      while i <= n: # taking 90% of negative tweets and writing them in f90 
       f90.write(line) 
       i += 1 
      while i != n: #putting the rest of the negative tweets (10%) in the f10 file 
       f10.write(line) 
       i += 1 
     elif line.startswith('1'): 
      while (x <= p): # taking 90% of positive tweets and writing them in f90 
       f90.write(line) 
       x += 1 
      while (x != p): #putting the rest of the positive tweets (10%) in the f10 file 
       f10.write(line) 
       x += 1   
     else: 
      print "Unmatched line ", line 

---

編輯

上述所有假設你已經成功地打開輸入文件確定。

注

" The backslash() character is used to escape characters that otherwise have a special meaning, such as newline, backslash itself, or the quote character. String literals may optionally be prefixed with a letter 'r' or 'R'; such strings are called raw strings and use different rules for interpreting backslash escape sequences"

從docs

您可以使用輸入文件與反斜線： 例如

f = open('C:\Users\Homura\Desktop\python\TData.txt' , 'r') 

嘗試改變這一個原始字符串

f = open(r'C:\Users\Homura\Desktop\python\TData.txt' , 'r')