在python中格式化/显示列表

Question

I'm new in python, I have a running code that extracts data from a web service and put it in a list and write it on a text file. When I run this code and open the text file, the data is continuous. I need something like in every line in text file, it will display 5 elements and will go to next line and write the next 5 elements and so on. Hope you can help me out on this or suggestion on other way to do this. Here's the code.

f = open("test.txt", "w")

for item in test:
    f.write("%s    |    " % item)
f.close()

The result looks like this:

data1, data2, data3, data4, data5, data6, data7, data8......................

It should be in this format:

data   |   data2   |   data3   |   data4   |
data5  |   data6   |   data7   |   data8   |
data9  |   data10  |   data11  |   data12  |

I hope I can have your inputs. Thank you!

Answer 1

Those characters aren't in the list, they are the list.

>>> print ''.join(['foo', 'bar', 'baz'])
foobarbaz

Answer 2

As @Ignacio said, you need to change the way you print the list.

for line in list_s:
    # f.write("%s\n" % line) 
    f.write(''.join(line))

If you'd like to display it in a table, you can format each row like this:

>>> print '{0:10s} {1:10s} {2:10s}'.format('foo', 'bar', 'baz')
foo        bar        baz       

Or with lines:

>>> print '{0:10s} | {1:10s} | {2:10s}'.format('foo', 'bar', 'baz')
foo        | bar        | baz    

See the Python Input and Output documentation for more information

Answer 3

for i, item in enumerate(test):
    if i and i % 4 == 0:
        f.write("\n")
    f.write("%-9s|   " % item)

Answer 4

What do you call "special characters"? What is the encoding of the data you have? Before proceeding, it is important for that you do understand what are encodings, what is unicode, and that the wrold, and data you get around is not restricted to the 26 letters primarily used in the English language. Check this article to learn about it.

That said, Python can encode your data in an encoding of your choice - even ASCII, so you only get the characters 32-127, and no "stranger" characters at all - like ã, ç, É - or you can encode your data in utf-8 to be able to use the whole array of characters we use around the planet. However, if you can only "encode" Unicode data (Python tries to implicit convert a byte string to unicode before if you use the encode string method) - so you do have to know the encoding of your data source anyway. Once your data is decoded into unicode (inside your running program), you can encode it to your desired output (eg ASCII or "quopri_codec" ), and set the "errors" keyword parameter to "ignore" or "xmlcharrefreplace" on your call to encode.

To understand it better, check the codecs documentation from Python

For example, assuming your input data is incoded in iso8859_15 (aka latin1 or cp1252 put or take 2 char definitions),a nd that you really mean to suppress any non-English character:

s = client.service.GetData('data1')
s = s.decode("iso88159_15").encode("ASCII", errors="ignore")
sr = '<root>%s</root>' % s
root = ET.fromstring(sr)

Otoh, since you are encoding xml, putting xml references to the chars you don't want to deal with should not hurt - (as probably encoding to utf-8 would not hurt either):

s = s.decode("iso88159_15").encode("ASCII", errors="xmlcharrefreplace")