我如何写一个列表文件?writelines()不插入换行符,所以我需要这样做:

f.writelines([f"{line}\n" for line in lines])

当前回答

在一般情况下

下面是writelines()方法的语法

fileObject.writelines( sequence )

例子

#!/usr/bin/python

# Open a file
fo = open("foo.txt", "rw+")
seq = ["This is 6th line\n", "This is 7th line"]

# Write sequence of lines at the end of the file.
line = fo.writelines( seq )

# Close opend file
fo.close()

参考

http://www.tutorialspoint.com/python/file_writelines.htm

其他回答

我想你在寻找这样的答案。

f = open('output.txt','w')
list = [3, 15.2123, 118.3432, 98.2276, 118.0043]
f.write('a= {:>3d}, b= {:>8.4f}, c= {:>8.4f}, d= {:>8.4f}, e= 
{:>8.4f}\n'.format(*list))
f.close()

更简单的是:

with open("outfile", "w") as outfile:
    outfile.write("\n".join(itemlist))

要确保项目列表中的所有项目都是字符串,请使用生成器表达式:

with open("outfile", "w") as outfile:
    outfile.write("\n".join(str(item) for item in itemlist))

记住,项目列表占用内存,所以要注意内存消耗。

在一般情况下

下面是writelines()方法的语法

fileObject.writelines( sequence )

例子

#!/usr/bin/python

# Open a file
fo = open("foo.txt", "rw+")
seq = ["This is 6th line\n", "This is 7th line"]

# Write sequence of lines at the end of the file.
line = fo.writelines( seq )

# Close opend file
fo.close()

参考

http://www.tutorialspoint.com/python/file_writelines.htm

使用循环:

with open('your_file.txt', 'w') as f:
    for line in lines:
        f.write(f"{line}\n")

对于Python <3.6:

with open('your_file.txt', 'w') as f:
    for line in lines:
        f.write("%s\n" % line)

对于Python 2,还可以使用:

with open('your_file.txt', 'w') as f:
    for line in lines:
        print >> f, line

如果您热衷于单个函数调用,至少要删除方括号[],以便每次生成一个要打印的字符串(genexp而不是listcomp)——没有理由占用物化整个字符串列表所需的所有内存。

将stdout重定向到一个文件也可以用于此目的:

from contextlib import redirect_stdout
with open('test.txt', 'w') as f:
  with redirect_stdout(f):
     for i in range(mylst.size):
        print(mylst[i])