windows环境下python中直接输出到txt文件的方法

Question

import itertools  

variations = itertools.product('abc', repeat=3)  
for variations in variations:  
    variation_string = ""  
    for letter in variations:  
        variation_string += letter  
    print (variation_string)  

如何将输出重定向到txt文件（在windows平台上）？

Answer 1

您还可以将stdout重定向到脚本中的文件，因为print默认情况下会写入sys.stdout文件处理程序。Python提供了一种简单的方法：

import sys  # Need to have acces to sys.stdout
fd = open('foo.txt','w') # open the result file in write mode
old_stdout = sys.stdout   # store the default system handler to be able to restore it
sys.stdout = fd # Now your file is used by print as destination 
print 'bar' # 'bar' is added to your file
sys.stdout=old_stdout # here we restore the default behavior
print 'foorbar' # this is printed on the console
fd.close() # to not forget to close your file

Answer 2

在控制台上，您可以编写：

python script.py > out.txt

如果你想用Python来完成，那么你可以写：

with open('out.txt', 'w') as f:
    f.write(something)

显然这只是一个微不足道的例子。很明显你会在with街区做更多的事。

Answer 3

如果是我，我会使用上面的David Heffernan方法将变量写入文本文件（因为其他方法需要用户使用命令提示符）。

import itertools  

file = open('out.txt', 'w')
variations = itertools.product('abc', repeat=3)  
for variations in variations:  
    variation_string = ""  
    for letter in variations:  
        variation_string += letter  
    file.write(variation_string)
file.close()